ACUS01 KWNS 080102
SWODY1
SPC AC 080100

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0800 PM CDT Tue Apr 07 2026

Valid 080100Z - 081200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Isolated thunderstorms remain possible tonight over the northern and
southern High Plains. Severe thunderstorms are not expected.

...Synopsis...
A mid-level trough continues to progress across the northern
Rockies, providing enough mechanical lift amid cool temperatures
aloft to support isolated high-based thunderstorms atop a dry
boundary layer. A low-amplitude mid-level impulse will also continue
to traverse the northern Rockies, supporting scattered lightning
flashes given the presence of scant buoyancy. These storms should
gradually diminish through the evening as boundary-layer
stabilization from nocturnal cooling takes place.

..Squitieri.. 04/08/2026

$$

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ACUS01 KWNS 080558
SWODY1
SPC AC 080556

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1256 AM CDT Wed Apr 08 2026

Valid 081200Z - 091200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
WESTERN AND CENTRAL KANSAS...

...SUMMARY...
A few strong thunderstorms may develop across western into central
Kansas this afternoon and evening, with an instance or two of severe
wind and hail possible.

...Synopsis...
A mid-level trough will traverse the north-central CONUS today,
supporting modest surface troughing across the Plains states.
Despite initially meager low-level moisture return, storms may
develop along a frontal boundary over the central Plains by late
afternoon. A few of which may be strong. Otherwise, isolated to
scattered thunderstorms may develop along sea-breeze boundaries over
the FL Peninsula, as was with the upper trough over the Upper MS
Valley. A couple of lightning flashes may also occur over northern
CA surrounding areas as an upper trough impinges on the coastline.

...Central into western Kansas...
By afternoon peak heating, clear skies and robust heating of the
boundary layer will result in convective temperatures being reached
along/just ahead of a frontal boundary, which is poised to drift
southward through late afternoon. Convective initiation is likely
around or after 20Z, when 30+ F T/Td spreads should be in place.
High-based multicells will be the likely storm mode, as strong
northwesterly flow aloft will contribute to elongated, straight
hodographs. The strongest storms may produce a couple of severe
gusts and perhaps an instance or two of hail.

..Squitieri/Chalmers.. 04/08/2026

$$

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ACUS01 KWNS 081247
SWODY1
SPC AC 081245

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0745 AM CDT Wed Apr 08 2026

Valid 081300Z - 091200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
KANSAS...

...SUMMARY...
Isolated severe thunderstorms may develop across western and central
Kansas late this afternoon and early evening, with hail and locally
severe wind gusts possible.

...Western/central Kansas...
The region will be glancingly influenced by an eastward-progressing
upper trough over the northern Plains. Ample insolation and robust
heating of a boundary layer, characterized by limited moisture (40s
F dewpoints), will result in convective temperatures being reached
by peak heating near a southeastward-moving front. Isolated to
widely scattered convective initiation is expected around or after
20Z, when 30+ F T/Td spreads will be in place. High-based multicells
will be the likely storm mode, as strong northwesterly flow aloft
will contribute to elongated, straight hodographs. The strongest
storms may produce hail and severe wind gusts on an isolated basis.

...Southern Florida...
A couple of stronger storms with gusty winds could again occur
today, mainly across the southeast part of the Florida Peninsula
this afternoon. Any severe threat should remain relatively marginal
and localized given the overall setup and thermodynamic environment.

..Guyer/Weinman.. 04/08/2026

$$

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ACUS01 KWNS 081612
SWODY1
SPC AC 081610

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1110 AM CDT Wed Apr 08 2026

Valid 081630Z - 091200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
KANSAS...

...SUMMARY...
Isolated severe thunderstorms may develop across parts of Kansas
late this afternoon and early evening, with hail and locally severe
wind gusts possible.

...Kansas...
A strong upper trough/low over the northern Plains and south-central
Canada will move eastward today towards the Upper Midwest/Great
Lakes, and eventually spread into Ontario by late tonight. At the
surface, an occluded low will develop eastward in tandem with the
upper trough/low, while a cold front extending southwestward into
the central Plains continues moving slowly southward through this
evening. Limited low-level moisture is expected to exist ahead of
the front by late this afternoon across KS, with late morning
surface observations and short-term guidance both suggesting surface
dewpoints will likely remain in the mid 30s to no more than mid 40s.
A well-mixed boundary layer will likely develop with ample daytime
heating across the narrow warm sector, with MLCAPE perhaps peaking
in the 250-500 J/kg range around 21-23Z in parts of western/central
KS. MLCIN is forecast to become minimal in this time frame, and weak
low-level convergence along the front may be enough to aid isolated thunderstorm development across this area.

While stronger flow aloft associated with the upper-level trough/low
will remain displaced to the north of KS, modest enhancement to the
mid-level westerlies may still support around 25-35 kt of deep-layer
shear. This should be sufficient for some updraft organization with
any thunderstorms that can develop and be sustained. The primary
uncertainty remains how many thunderstorms will form given overall
modest large-scale ascent amid weak instability. Still, some risk
for isolated hail and locally severe gusts remains apparent with the
strongest multicell cores. The Marginal Risk has been maintained
across KS with no changes.

...Central/South Florida...
20-30 kt mid-level westerlies will overlie weak low-level easterlies
today across parts of the central/southern Florida Peninsula.
Resultant modest effective bulk shear would conditionally support
updraft organization, but poor mid-level lapse rates noted on the
12Z TBW and KEY observed soundings should generally limit updraft
strength. Still, isolated to locally scattered thunderstorms should
develop this afternoon, and preferentially focus along/near the
Atlantic Coast sea breeze. Small hail and gusty winds may occur with
the strongest cores, but the overall severe threat appears too
limited/isolated to include any probabilities at this time.

..Gleason/Wendt.. 04/08/2026

$$

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ACUS01 KWNS 081948
SWODY1
SPC AC 081946

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0246 PM CDT Wed Apr 08 2026

Valid 082000Z - 091200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS WESTERN
AND CENTRAL KANSAS...

...SUMMARY...
Isolated severe thunderstorms may develop across parts of Kansas
late this afternoon and early evening, with hail and locally severe
wind gusts possible.

...20z Update KS...
The prior outlook remains valid with no changes. High-based
thunderstorms remain possible late this afternoon and this evening
ahead of the cold front in western and central KS. Steep low and
mid-level lapse rates should be sufficient for modest
destabilization amid limited boundary-layer moisture (dewpoints in
the 40s F). Despite the limited buoyancy, a few stronger multi-cell
clusters capable of isolated severe gusts and some small hail are
possible.

Elsewhere, isolated thunderstorms remain possible across parts of
FL, the West Coast and northern Plains through tonight. Weak
buoyancy and poor overlap with vertical shear should limit severe
potential. See the previous discussion for more information.

..Lyons.. 04/08/2026

.PREV DISCUSSION... /ISSUED 1110 AM CDT Wed Apr 08 2026/

...Kansas...
A strong upper trough/low over the northern Plains and south-central
Canada will move eastward today towards the Upper Midwest/Great
Lakes, and eventually spread into Ontario by late tonight. At the
surface, an occluded low will develop eastward in tandem with the
upper trough/low, while a cold front extending southwestward into
the central Plains continues moving slowly southward through this
evening. Limited low-level moisture is expected to exist ahead of
the front by late this afternoon across KS, with late morning
surface observations and short-term guidance both suggesting surface
dewpoints will likely remain in the mid 30s to no more than mid 40s.
A well-mixed boundary layer will likely develop with ample daytime
heating across the narrow warm sector, with MLCAPE perhaps peaking
in the 250-500 J/kg range around 21-23Z in parts of western/central
KS. MLCIN is forecast to become minimal in this time frame, and weak
low-level convergence along the front may be enough to aid isolated thunderstorm development across this area.

While stronger flow aloft associated with the upper-level trough/low
will remain displaced to the north of KS, modest enhancement to the
mid-level westerlies may still support around 25-35 kt of deep-layer
shear. This should be sufficient for some updraft organization with
any thunderstorms that can develop and be sustained. The primary
uncertainty remains how many thunderstorms will form given overall
modest large-scale ascent amid weak instability. Still, some risk
for isolated hail and locally severe gusts remains apparent with the
strongest multicell cores. The Marginal Risk has been maintained
across KS with no changes.

...Central/South Florida...
20-30 kt mid-level westerlies will overlie weak low-level easterlies
today across parts of the central/southern Florida Peninsula.
Resultant modest effective bulk shear would conditionally support
updraft organization, but poor mid-level lapse rates noted on the
12Z TBW and KEY observed soundings should generally limit updraft
strength. Still, isolated to locally scattered thunderstorms should
develop this afternoon, and preferentially focus along/near the
Atlantic Coast sea breeze. Small hail and gusty winds may occur with
the strongest cores, but the overall severe threat appears too
limited/isolated to include any probabilities at this time.

$$

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ACUS01 KWNS 090058
SWODY1
SPC AC 090056

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0756 PM CDT Wed Apr 08 2026

Valid 090100Z - 091200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Severe thunderstorms are not expected through tonight.

...Discussion...
The Marginal Risk across western/central Kansas was removed with
this outlook update. A cluster of thunderstorm activity continues to
shift south and east, but has largely remained below severe limits.
This activity is expected to further weaken over the next couple of
hours with the loss of daytime heating and gradually waning MLCAPE.

..Thornton.. 04/09/2026

$$

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ACUS01 KWNS 090559
SWODY1
SPC AC 090557

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1257 AM CDT Thu Apr 09 2026

Valid 091200Z - 101200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS CENTRAL/NORTHEAST
KANSAS INTO SOUTHEAST NEBRASKA AND NORTHWEST MISSOURI...

...SUMMARY...
Areas of hail and strong wind gusts are expected this afternoon and
evening in parts of the lower to mid Missouri Valley westward into
Kansas. Locally very large hail is possible.

...Synopsis...
The upper-level pattern across the US today will consist of a
deepening trough across the Western US with enhanced westerly flow
extending across the central/northern US within the base of a
broader upper-low across portions of Canada. Within the broad area
of westerly flow, several disturbances will rotate across the
northern Plains into the Great Lakes Region.

At the surface, a warm front will lift northward through the day
across the central Plains, extending as far north as southern NE/IA.
As a surface high builds to the north across the Dakotas, this
boundary will sag southward as a cold front through the late
afternoon/evening. Scattered thunderstorm development is expected
along this east/west oriented boundary and as well across the
dryline further west into the OK/TX Panhandles. The primary threat
will be for large to very large hail and damaging wind. A more
isolated risk for large hail will extend southward across the
dryline into western Kansas/OK/TX Panhandles.

...Central Plains...
South of the aforementioned boundary across central KS into
southeastern NE, low to mid-50s dew points in combination with
strong daytime heating will yield moderate MLCAPE values around
1000-1500 J/kg. Thunderstorm activity should develop along the warm
front around 18z and increase with the incoming upper-level wave and
cooling aloft. Forecast soundings along and south of the boundary in
Kansas depict steep low to mid-level lapse rates (7-8 C/km) and deep
layer shear around 40 kts, supportive of supercells capable of large
to very large hail(some 2+ inches in diameter)and severe wind. The
Slight was extended southward into central Kansas to account for
potential for development into this region and continuation of the
large to very large hail threat.

With west to northwest winds aloft, all these storms may eventually
merge into the evening, propagating southeastward across much of
eastern KS into northwest MO. The warm boundary layer, combined with
cold downdraft material, will likely support scattered damaging
gusts.

...Northern California/Oregon Coasts...
As the upper-level low approaches the West Coast, forcing for ascent
will overspread portions of northern California into southern Oregon
with scattered thunderstorm development expected by the late
morning/afternoon. Sufficient moisture and MLCAPE will extend inland overlapping deep layer shear 20-25 kts and steep low to mid-level
lapse rates to support potential for strong to severe wind gusts. As
such, a 5% wind area was introduced with this outlook to cover this
potential. Some instances of small hail will also be possible, owing
to steep lapse rates and cooling temperatures aloft.

..Thornton/Chalmers.. 04/09/2026

$$

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ACUS01 KWNS 091252
SWODY1
SPC AC 091250

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0750 AM CDT Thu Apr 09 2026

Valid 091300Z - 101200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL
PLAINS AND LOWER/MIDDLE MISSOURI VALLEY...

...SUMMARY...
Severe storms capable of large hail and severe wind gusts are
expected late this afternoon and evening across Kansas, southeast
Nebraska into northwest Missouri and southwest Iowa. Isolated severe
storms may also occur across the south-central High Plains and
northern California/western Oregon.

...Central Plains and Lower/Middle Missouri Valley...
A frontal zone will focus and shift northward toward across Kansas
toward the Kansas/Nebraska and Iowa/Missouri border vicinities
today, before gradually accelerating southeastward tonight. The
region will be influenced later today by a secondary shortwave
trough digging southeastward over the northern Plains, with the
persistence of cyclonic and somewhat strengthening mid/upper-level
flow. On the nose of south-southwesterly lower tropospheric winds,
low-level moisture will diurnally increase along/south of the front,
offset by ample mixing across Kansas, resulting in surface dewpoints
mainly in the lower/middle 50s F into peak heating. Beneath very
steep mid-level lapse rates, 1000-1500 J/kg MLCAPE values are
expected near/south of the front.

After some early day thunderstorms, more intense surface-based
thunderstorm development should occur as early as 22-23z/5-6pm CDT
near the boundary including portions of northern Kansas/southeast
Nebraska to the Iowa/Missouri border region, with other more
isolated and higher-based storms possible across western Kansas and
the nearby High Plains in vicinity of the lee trough/surface low.

Moderately strong westerlies will reside along/north of the
boundary, with 40+ kt effective shear supporting supercells capable
of large hail, potentially some in excess of 2 inches in diameter.
Some tornado potential may exist mainly across northeast Kansas/far
southeast Nebraska and northwest Missouri near the boundary, but
this overall potential will tend to be mitigated by modest-caliber
moisture and the influence of diurnal mixing. Severe winds are also
possible into evening as storms tend to cluster and spread/increase east-southeastward during the evening, although the modest early
season moisture and nocturnal influences will lead to a diminished
intensity trend into late evening.

...Northern California/western Oregon...
As the upper-level low approaches the West Coast, forcing for ascent
will overspread portions of northern California into southern Oregon
with scattered thunderstorm development expected into afternoon.
Sufficient moisture and CAPE will exist inland beneath strengthening
deep-layer southwesterly winds ahead of the trough. As lapse rates
steepen and flow aloft increases, storms may be capable of strong to
severe wind gusts and possibly some hail.

..Guyer/Weinman.. 04/09/2026

$$

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ACUS01 KWNS 091630
SWODY1
SPC AC 091628

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1128 AM CDT Thu Apr 09 2026

Valid 091630Z - 101200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
KANSAS INTO SOUTHEAST NEBRASKA AND NORTHWEST MISSOURI...

...SUMMARY...
Severe thunderstorms capable of producing large hail and severe wind
gusts are expected late this afternoon and evening across parts of
Kansas, southeast Nebraska, and northwest Missouri. Isolated severe thunderstorms may also occur across portions of the south-central
High Plains and northern California/southwest Oregon.

...Southern High Plains into the Central Plains and Lower/Mid
Missouri Valley...
Ongoing precipitation/thunderstorms and related cloud cover across north-central/northeast KS into southeast NE/southwest IA is being
aided by modest low-level warm/moist advection in the vicinity of a
surface front. Current expectations are for this activity to
gradually diminish in coverage as it shifts eastward into the
northwest MO/southern IA. In its wake, daytime heating may be
hampered a bit by residual cloudiness across much of
north-central/northeast KS. Even so, continued northward low-level
moisture advection is anticipated across the southern/central Plains
through the afternoon, with surface dewpoints generally in the upper
40s to low/mid 50s. This, coupled with steep mid-level lapse rates
and cold temperatures aloft, will aid in the development of moderate instability (MLCAPE around 1000-1500 J/kg) along/south of a front
draped generally west to east across northern KS/MO.

Stronger ascent aloft and enhanced westerly flow at mid/upper levels
will remain mostly displaced to the north of the central Plains
today, as multiple mid-level perturbations rotate through mean
mid/upper-level troughing over central/eastern Canada. Still, most
guidance continues to suggest that minimal MLCIN will exist in the
vicinity of the front in north-central/northeast KS and southeast NE
by 22-23Z as surface temperatures warm into the 70s/low 80s.
Isolated to scattered thunderstorms are expected to develop across
this area by late afternoon/early evening, with modest
south-southwesterly low-level winds veering to west-northwesterly at
mid/upper levels supporting 35-45 kt of deep-layer shear.

Initial convective development will likely be supercellular and pose
a threat for mainly large hail (isolated 2+ inches in diameter
possible). Fairly large surface temperature-dewpoint spreads with a
well-mixed boundary layer and related high cloud bases render
considerable uncertainty regarding tornado potential. But, some risk
for a tornado or two may focus along/near the front through early
evening as effective SRH gradually increases in tandem with a
strengthening south-southwesterly low-level jet. Otherwise, the risk
for severe/damaging winds may gradually increase through mid evening
as thunderstorms tend to cluster/grow modestly upscale. But, the
severe wind risk will likely become more limited by late evening
with the loss of daytime heating and increasing MLCIN with
southward/eastward extent.

Isolated thunderstorms may also develop this afternoon farther
southwest across the central/southern High Plains along and east of
a sharpening surface dryline/lee trough. Overall convective coverage
remains highly uncertain given nebulous/weak large-scale ascent this
far south. Still, some risk for occasional hail and severe gusts
should exist with any sustained cells or clusters that can develop
and spread east-southeastward through the late afternoon/early
evening.

...Northern California/Southwest Oregon...
As an upper-level low over the eastern Pacific approaches the West
Coast today, large-scale ascent will overspread portions of northern
CA into southern OR with scattered thunderstorm development expected
into afternoon. Sufficient moisture and instability should exist
inland beneath strengthening deep-layer southwesterly winds ahead of
the trough to support semi-organized convection. As low-level lapse
rates gradually steepen and flow aloft increases, this activity may
be capable of producing isolated strong to severe gusts and possibly
some hail.

..Gleason/Wendt.. 04/09/2026

$$

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ACUS01 KWNS 091945
SWODY1
SPC AC 091943

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0243 PM CDT Thu Apr 09 2026

Valid 092000Z - 101200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PORTIONS OF
CENTRAL AND NORTHEAST KANSAS INTO SOUTHERN NEBRASKA AND FAR
NORTHWEST MISSOURI...

...SUMMARY...
Severe thunderstorms capable of producing large hail and severe wind
gusts are expected late this afternoon and evening across parts of
Kansas, southeast Nebraska, and northwest Missouri. Isolated severe thunderstorms may also occur across portions of the south-central
High Plains and northern California/southwest Oregon.

...20z Update central and southern Plains...
Thunderstorm development remains likely late this afternoon and this
evening along the frontal zone from southern NE into northeast KS.
While remnant cloud cover has slowed destabilization, sufficient
buoyancy and supercell wind profiles will likely support a risk for
hail, damaging gusts and perhaps a tornado or two this
afternoon/evening. See MCD #367 for specific short-term information.

Farther south along the trailing surface trough/dryline, more
isolated thunderstorm development is expected across the TX
Panhandle and far eastern NM. High cloud bases with deep inverted-v
structures could support isolated severe wind gusts with the heavier
cores. Storm coverage is likely to decrease farther south where
weaker forcing and overall more limited buoyancy is present. Still,
isolated storms are possible, and the 5% wind area was expanded
southward slightly for the latest hi-res guidance.

...CA and OR...
East of an upper low, broad-scale ascent over a modestly warm/moist
air mass was supporting widely scattered thunderstorms over portions
of northern CA and southern OR. While overall buoyancy is weak
(generally below 500 J/kg of MLCAPE), strengthening southerly flow
aloft could support a few organized clusters or transient supercells
capable of producing isolated strong to severe gusts and some hail.

..Lyons.. 04/09/2026

.PREV DISCUSSION... /ISSUED 1128 AM CDT Thu Apr 09 2026/

...Southern High Plains into the Central Plains and Lower/Mid
Missouri Valley...
Ongoing precipitation/thunderstorms and related cloud cover across north-central/northeast KS into southeast NE/southwest IA is being
aided by modest low-level warm/moist advection in the vicinity of a
surface front. Current expectations are for this activity to
gradually diminish in coverage as it shifts eastward into the
northwest MO/southern IA. In its wake, daytime heating may be
hampered a bit by residual cloudiness across much of
north-central/northeast KS. Even so, continued northward low-level
moisture advection is anticipated across the southern/central Plains
through the afternoon, with surface dewpoints generally in the upper
40s to low/mid 50s. This, coupled with steep mid-level lapse rates
and cold temperatures aloft, will aid in the development of moderate instability (MLCAPE around 1000-1500 J/kg) along/south of a front
draped generally west to east across northern KS/MO.

Stronger ascent aloft and enhanced westerly flow at mid/upper levels
will remain mostly displaced to the north of the central Plains
today, as multiple mid-level perturbations rotate through mean
mid/upper-level troughing over central/eastern Canada. Still, most
guidance continues to suggest that minimal MLCIN will exist in the
vicinity of the front in north-central/northeast KS and southeast NE
by 22-23Z as surface temperatures warm into the 70s/low 80s.
Isolated to scattered thunderstorms are expected to develop across
this area by late afternoon/early evening, with modest
south-southwesterly low-level winds veering to west-northwesterly at
mid/upper levels supporting 35-45 kt of deep-layer shear.

Initial convective development will likely be supercellular and pose
a threat for mainly large hail (isolated 2+ inches in diameter
possible). Fairly large surface temperature-dewpoint spreads with a
well-mixed boundary layer and related high cloud bases render
considerable uncertainty regarding tornado potential. But, some risk
for a tornado or two may focus along/near the front through early
evening as effective SRH gradually increases in tandem with a
strengthening south-southwesterly low-level jet. Otherwise, the risk
for severe/damaging winds may gradually increase through mid evening
as thunderstorms tend to cluster/grow modestly upscale. But, the
severe wind risk will likely become more limited by late evening
with the loss of daytime heating and increasing MLCIN with
southward/eastward extent.

Isolated thunderstorms may also develop this afternoon farther
southwest across the central/southern High Plains along and east of
a sharpening surface dryline/lee trough. Overall convective coverage
remains highly uncertain given nebulous/weak large-scale ascent this
far south. Still, some risk for occasional hail and severe gusts
should exist with any sustained cells or clusters that can develop
and spread east-southeastward through the late afternoon/early
evening.

...Northern California/Southwest Oregon...
As an upper-level low over the eastern Pacific approaches the West
Coast today, large-scale ascent will overspread portions of northern
CA into southern OR with scattered thunderstorm development expected
into afternoon. Sufficient moisture and instability should exist
inland beneath strengthening deep-layer southwesterly winds ahead of
the trough to support semi-organized convection. As low-level lapse
rates gradually steepen and flow aloft increases, this activity may
be capable of producing isolated strong to severe gusts and possibly
some hail.

$$

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ACUS01 KWNS 100102
SWODY1
SPC AC 100100

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0800 PM CDT Thu Apr 09 2026

Valid 100100Z - 101200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF CENTRAL/NORTHEAST KS INTO FAR SOUTHEAST NE/NORTHWEST MO...

...SUMMARY...
Severe thunderstorms capable of producing large hail and severe wind
gusts remain possible this evening across parts of Kansas, southeast
Nebraska, and northwest Missouri.

...Central/southern Plains...
Scattered strong to severe storms have developed this evening from
southwest into north-central KS and far southern NE this evening,
near/south of a southward-moving cold front, and along/east of a
weak dryline. Despite modest low-level moisture (with warm-sector
dewpoints generally in the low 50s F), steep midlevel lapse rates
and relatively cold temperatures aloft are supporting MLCAPE of
1000-1500 J/kg, within a moderately sheared environment.

A few relatively high-based supercells remain possible through the
evening, with an attendant threat of large hail (potentially
golf-ball-sized or larger) and localized severe gusts. A tornado
also cannot be ruled out across north-central/northeast KS, as
low-level moisture/shear gradually improve in conjunction with a
nocturnal low-level jet. Otherwise, some upscale growth remains
possible with time, which could result in at least an isolated
severe-wind threat spreading across parts of northeast KS and
northwest MO later tonight, before the threat diminishes in response
to increasing MLCINH. See MCD 370 and MD 371 for more information
regarding the short-term severe threat in this area.

...Northwest CA/southwest OR vicinity...
A few strong storms remain possible through early evening across
parts of northwest CA and southwest OR, in association with an upper
low off of the northern CA coast. Any remaining severe threat should
tend to diminish with time, as already weak buoyancy further
decreases due to convective overturning and nocturnal stabilization.

...CA Central Valley...
Isolated strong storms have recently developed across parts of the
CA central valley, with a supercell noted northwest of Fresno. While
deep-layer flow is rather weak, MUCAPE of 500-1000 J/kg and modest
veering of the wind profile could support a very isolated threat of
gusty winds and small to marginally severe hail, though coverage and
duration of the threat are expected to remain limited.

..Dean.. 04/10/2026

$$

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ACUS01 KWNS 100555
SWODY1
SPC AC 100553

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1253 AM CDT Fri Apr 10 2026

Valid 101200Z - 111200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE SOUTH-CENTRAL PLAINS INTO THE OZARKS...NORTHERN NV INTO SOUTHEAST
OR/SOUTHWEST ID...AND PARTS OF CENTRAL CA...

...SUMMARY...
Thunderstorms with isolated large hail and severe gusts will be
possible this afternoon and evening from parts of the south-central
Plains into the Ozarks. Strong to locally severe storms may also
occur from northern Nevada into southeast Oregon and southwest
Idaho, and also across parts of central California.

...Synopsis...
A mid/upper-level shortwave trough will move from the Great Lakes
region toward New England through the period. Upstream, a mid/upper
low initially offshore of California will move inland toward the
Great Basin as a shortwave trough, as another mid/upper
shortwave/low approaches the Pacific Coast.

...Parts of the south-central Plains into the Ozarks...
In the wake of morning elevated convection, an outflow-reinforced
cold front is expected to become nearly stationary this afternoon
and early evening. Steep midlevel lapse rates and rather cool
temperatures aloft will support MLCAPE of near/above 1500 J/kg
along/south of the front, with minimal MLCINH by afternoon.
Scattered thunderstorms are expected to develop by late afternoon in
the vicinity of the boundary across parts of southern KS/northern OK
into the Ozarks, with additional development possible near the front
and within a post-frontal regime across the south-central High
Plains vicinity.

With rather modest large-scale ascent and weak deep-layer flow
forecast across the region, storm organization and duration may
generally remain somewhat limited. However, more organized cells may
briefly develop on an isolated basis near the boundary, where some
enhancement to effective shear/SRH will be possible. Isolated large
hail appears to be the most likely hazard, though localized
strong/damaging gusts also cannot be ruled out with the strongest
storms.

...Northern NV into southeast OR/southwest ID and central/northern
CA...
In response to the approaching mid/upper low and shortwave trough,
scattered thunderstorm development is expected this afternoon across
parts of central/northern CA into the northern Great Basin and
interior Northwest. Cold temperatures aloft and rather strong
diurnal heating will result in steep low/midlevel lapse rates and
MUCAPE increasing to near/above 500 J/kg, despite limited low-level
moisture.

Midlevel flow and deep-layer shear will gradually increase with
time, with the most favorable overlap of shear and instability
currently expected from northern NV into southeast OR/southwest ID.
Modestly organized cells/clusters and perhaps a couple of supercells
may develop in this area, with an attendant threat of hail and
localized severe gusts.

A few strong storms may also develop across parts of the Sacramento
and northern San Joaquin Valleys in California. While deep-layer
shear will be somewhat less favorable compared to the northern Great
Basin area, cold temperatures aloft (near/below -20C at 500 mb) may
support potential for marginally severe hail with the strongest
storms. Local terrain influences could also support transient cell organization/rotation and possibly a brief tornado, though this
potential remains very uncertain at this time.

..Dean/Chalmers.. 04/10/2026

$$

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ACUS01 KWNS 101237
SWODY1
SPC AC 101236

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0736 AM CDT Fri Apr 10 2026

Valid 101300Z - 111200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE SOUTH-CENTRAL PLAINS/OZARKS AND NORTHERN CALIFORNIA/GREAT
BASIN...

...SUMMARY...
Thunderstorms with isolated large hail and severe gusts are possible
this afternoon and evening across parts of the south-central Plains
to the Ozarks. Strong to locally severe storms may also occur from western/northern Nevada into southeast Oregon and southwest Idaho,
and also across parts of north-central California.

...South-central Plains/Ozarks...
Scattered rain and generally weak thunderstorms will continue to
accompany and reinforce a southward-shifting front, with the
boundary stalling today, before starting to shift back northward
late tonight. Weakening flow aloft will occur today in the presence
of a building upper ridge and corresponding height rises. As
outflows dissipate, ample heating/mixing is expected later today to
the south of the front, where MLCAPE values may exceed 1500 J/kg
across Oklahoma/Texas Panhandle and northeast New Mexico.

Even with modest overall forcing for ascent, scattered thunderstorms
are expected to develop by late afternoon in the vicinity of the
boundary across parts of far southern Kansas/northern Oklahoma into
the Ozarks, with additional development possible near the front, and
also within a post-frontal regime across the south-central High
Plains vicinity.

With rather modest large-scale ascent and weak deep-layer flow
across the region, storm organization and duration may generally
remain somewhat limited. However, more organized cells may briefly
develop on an isolated basis more immediately near the boundary,
where some enhancement to effective shear/SRH will be possible.
Isolated large hail appears to be the most likely hazard, although
localized strong/damaging wind gusts could also occur.

...Nevada/southeast OR/southwest ID and north-central CA...
A closed upper low off the coast of northern California will open
and become more progressive, reaching the Sierra and parts of the
Great Basin tonight. Related forcing for ascent and moisture will
influence scattered thunderstorm development this afternoon across
parts of central/northern California into the northern Great Basin
and interior Northwest. Cold temperatures aloft and rather strong
diurnal heating will result in steep low/mid-level lapse rates and
MUCAPE increasing to near/above 500 J/kg.

Mid-level flow and deep-layer shear will gradually increase over
time, with the most favorable overlap of vertical shear and
instability expected across western/northern Nevada into southeast
Oregon and southwest Idaho. Semi-organized cells/clusters, and
perhaps even a few supercells, may develop with an attendant threat
of hail and localized severe wind gusts.

A few locally severe storms may also develop across parts of the
Sacramento and northern San Joaquin Valleys in California this
afternoon. While deep-layer shear will be somewhat weaker as
compared to the northern Great Basin, cold temperatures aloft
(near/below -20C at 500 mb) may support marginally severe hail with
the strongest storms. The steep lapse rate environment and local
terrain influences could also support transient cell rotation and
possibly funnels, or even a brief tornado, although this potential
currently seems low/uncertain.

..Guyer/Broyles.. 04/10/2026

$$

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ACUS01 KWNS 101631
SWODY1
SPC AC 101630

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1130 AM CDT Fri Apr 10 2026

Valid 101630Z - 111200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE SOUTH-CENTRAL PLAINS/OZARKS...NORTHERN CALIFORNIA/GREAT
BASIN...AND WESTERN OREGON...

...SUMMARY...
Thunderstorms with isolated large hail and severe gusts are possible
this afternoon and evening across parts of the south-central Plains
to the Ozarks. Strong to locally severe storms may also occur from western/northern Nevada into southeast Oregon and southwest Idaho,
and also across parts of north-central California.

...Southern High Plains/South-central Plains into the Ozarks...
Recent surface analysis places a low over the western TX Panhandle,
with a cold front extending east-northeastward from this low across
northwest and north-central OK, and far southeast KS, before
becoming oriented more northeastward across southern and central MO.
Showers and thunderstorms are ongoing in the vicinity of this
boundary, as well modest southeastward-progressing outflow, across
far southern KS and northern OK.

The cold front is forecast to trend more stationary throughout the
day as heights rise across the Plains and southerly low-level flow
persists across the southern Plains, with the outflow following this
trend as well. After 06Z, this stationary boundary will likely begin
shifting back northward into southern KS as warm front. Additional
thunderstorm development is possible amid low-level convergence near
both the stationary front and outflow as the airmass modestly
destabilizes this afternoon. Isolated damaging gusts and/or
marginally severe hail is possible with the strongest storms, but
modest shear and buoyancy suggests most storms will be sub-severe.

Farther west, low-level convergence along a sharpening lee trough
may contribute to late afternoon thunderstorm development across the
southern High Plain, particularly northeast NM. High cloud bases and
steep low-level lapse rates support the potential for strong
downbursts with any deep/more persistent updrafts. Some interaction
with the western extent of the frontal zone is possible as well,
which could briefly enhance updrafts, contributing to a continued
potential for damaging gusts as well as isolated hail.

...North-central CA/western OR into the northern Great Basin...
Upper low currently centered just off the northern/central CA coast
is forecast to become more progressive and negatively tilted
throughout the day today. Mid-level moisture and ascent attendant to
this wave will support scattered thunderstorm development this
afternoon from central/northern CA and western OR into the northern
Great Basin and interior Northwest. Cold temperatures aloft (i.e.
-20 deg C at 500 mb) and strong diurnal heating will result in steep low/mid-level lapse rates and at least modest buoyancy across much
of the region.

A few areas (interior valley of central CA, Willamette Valley in OR,
and northern NV/southwest OR/southern ID) appear to have a slightly
higher potential for isolated strong to severe storms, largely a
result of more diurnal heating/higher afternoon temperatures.
Greater buoyancy combined with moderate/strong deep-layer shear will
support semi-organized cells/clusters, and perhaps even a few
supercells, may develop with an attendant threat of hail and
localized severe wind gusts. Deep-layer shear will be a bit weaker
across the interior valley of central CA but still sufficient for a
few organized storms. The steep lapse rate environment and local
terrain influences could also support transient cell rotation and
possibly funnels, or even a brief tornado.

..Mosier/Squitieri.. 04/10/2026

$$

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ACUS01 KWNS 101953
SWODY1
SPC AC 101952

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0252 PM CDT Fri Apr 10 2026

Valid 102000Z - 111200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF
OREGON...THE CENTRAL VALLEY OF CALIFORNIA...THE GREAT BASIN AND
SOUTHERN PLAINS/OZARKS...

...SUMMARY...
Thunderstorms with isolated large hail and severe gusts remain
possible this afternoon and evening across parts of the
south-central Plains to the Ozarks. Strong to locally severe storms
may also occur from western/northern Nevada into southeast Oregon
and southwest Idaho, and also across parts of north-central
California.

...20z Update...
Minimal changes were made to the prior outlook. A prominent
differential heating/outflow boundary associated with a cluster of thunderstorms over OK is forecast to continue sagging southward this
afternoon. An increase in storm coverage is possible this afternoon
and evening associated with the ongoing cluster and the trailing
boundary. With moderate buoyancy weak vertical shear, a low-end risk
for damaging gusts and hail could develop. 5% wind and hail
probabilities have been expanded slightly farther southeastward.

To the West across the Great Basin, strong mid-level ascent ahead of
the upper low over the Pacific Coast was overspreading a marginally
moist and buoyant air mass across parts of NV. Strong southerly flow
aloft could support a few semi-organized storms or clusters capable
of damaging gusts and sporadic hail. 5% wind and hail probabilities
have been expanded southward over parts of NV where buoyancy and
shear overlap could support some severe potential.

Otherwise, isolated severe storms remain possible across parts of
the central Valley of CA and western OR. The forecast remains
unchanged, see the prior discussion for more information.

..Lyons.. 04/10/2026

.PREV DISCUSSION... /ISSUED 1130 AM CDT Fri Apr 10 2026/

...Southern High Plains/South-central Plains into the Ozarks...
Recent surface analysis places a low over the western TX Panhandle,
with a cold front extending east-northeastward from this low across
northwest and north-central OK, and far southeast KS, before
becoming oriented more northeastward across southern and central MO.
Showers and thunderstorms are ongoing in the vicinity of this
boundary, as well modest southeastward-progressing outflow, across
far southern KS and northern OK.

The cold front is forecast to trend more stationary throughout the
day as heights rise across the Plains and southerly low-level flow
persists across the southern Plains, with the outflow following this
trend as well. After 06Z, this stationary boundary will likely begin
shifting back northward into southern KS as warm front. Additional
thunderstorm development is possible amid low-level convergence near
both the stationary front and outflow as the airmass modestly
destabilizes this afternoon. Isolated damaging gusts and/or
marginally severe hail is possible with the strongest storms, but
modest shear and buoyancy suggests most storms will be sub-severe.

Farther west, low-level convergence along a sharpening lee trough
may contribute to late afternoon thunderstorm development across the
southern High Plain, particularly northeast NM. High cloud bases and
steep low-level lapse rates support the potential for strong
downbursts with any deep/more persistent updrafts. Some interaction
with the western extent of the frontal zone is possible as well,
which could briefly enhance updrafts, contributing to a continued
potential for damaging gusts as well as isolated hail.

...North-central CA/western OR into the northern Great Basin...
Upper low currently centered just off the northern/central CA coast
is forecast to become more progressive and negatively tilted
throughout the day today. Mid-level moisture and ascent attendant to
this wave will support scattered thunderstorm development this
afternoon from central/northern CA and western OR into the northern
Great Basin and interior Northwest. Cold temperatures aloft (i.e.
-20 deg C at 500 mb) and strong diurnal heating will result in steep low/mid-level lapse rates and at least modest buoyancy across much
of the region.

A few areas (interior valley of central CA, Willamette Valley in OR,
and northern NV/southwest OR/southern ID) appear to have a slightly
higher potential for isolated strong to severe storms, largely a
result of more diurnal heating/higher afternoon temperatures.
Greater buoyancy combined with moderate/strong deep-layer shear will
support semi-organized cells/clusters, and perhaps even a few
supercells, may develop with an attendant threat of hail and
localized severe wind gusts. Deep-layer shear will be a bit weaker
across the interior valley of central CA but still sufficient for a
few organized storms. The steep lapse rate environment and local
terrain influences could also support transient cell rotation and
possibly funnels, or even a brief tornado.

$$

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ACUS01 KWNS 110059
SWODY1
SPC AC 110058

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0758 PM CDT Fri Apr 10 2026

Valid 110100Z - 111200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Isolated to scattered thunderstorms remain possible during the late
evening hours across parts of the southern Plains and Great Basin;
however, the overall severe risk appears limited.

...Southern Plains...
Latest MRMS imagery depicts steady weakening of convection across
northeast NM and across northern OK with the onset of nocturnal
cooling and expanding convective outflows. While a couple of
stronger storms are noted across far eastern NM and southwest TX,
weak deep-layer wind shear and diminishing buoyancy should favor a
weakening trend heading into the late evening hours.

Additional elevated thunderstorms are anticipated well north of the
stalled surface boundary along the OK/KS border with recent CAM
guidance suggesting multi-cell clusters developing across portions
of central to northeast KS after 03 UTC. The recent 00z DDC RAOB
likely sampled the environment this convection will develop in, and
hints that at least a small hail threat may materialize with
initially discrete cells prior to upscale growth within the first
couple of hours after initiation.

...Great Basin...
Similar to the southern Plains, convective trends have largely shown
signs of weakening over the past hour across central to northern NV
where surface temperatures are quickly cooling into the 60s. The
combination of rain-cooled air/outflows and the onset of nocturnal
cooling should further reduce any remaining mixed-layer buoyancy
(which was already fairly marginal per regional 00z RAOBs).
Consequently, the thermodynamic environment no longer appears
supportive of intense convection, though a strong storm or two may
persist for the next hour as the boundary layer continues to
stabilize.

..Moore.. 04/11/2026

$$

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ACUS01 KWNS 110543
SWODY1
SPC AC 110542

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1242 AM CDT Sat Apr 11 2026

Valid 111200Z - 121200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
THE SOUTHERN HIGH PLAINS...

...SUMMARY...
Scattered thunderstorms producing hail and strong wind gusts will be
possible across portions of the southern High Plains this afternoon
and evening. More isolated strong to severe thunderstorms are
expected across parts of the central Rockies, central Plains, upper
Mississippi Valley, and portions of the California coast.

...Synopsis...
An upper trough is evident in early-morning water-vapor imagery off
the California Coast. This wave will gradually de-amplify over the
next 24 hours as it progresses northeastward into the northern
Rockies. Further south, a lower-amplitude upper disturbance is noted
off the coast of Baja CA, and will migrate northeast into southwest
TX through this evening. Ahead of these features, modest lee
troughing along the High Plains and the southeastward shift of
surface high from the Midwest into the upper OH Valley will yield an
extended fetch of southerly low-level flow from the TX coast into
the upper MS Valley, resulting in northward moisture return as well
as a broad zone of isentropic ascent from the Plains into the upper
MS Valley.

...Southern High Plains...
Thunderstorm development appears likely by mid-afternoon across
southwest TX as ascent associated with the upper disturbance off the
coast of Baja CA migrates out of northern Mexico and overspreads
returning moisture. Initially discrete cells are likely and will
pose a threat for large hail given adequate deep-layer wind shear.
However, weak capping and strong ascent should promote upscale
growth by early evening into one or more convective lines. As this
transition occurs, strong to severe wind gusts will become the
predominant hazard, though an embedded circulation or two may be
possible. Based on latest guidance, the wind/tornado threat may be
maximized along and south of the I-20 corridor where the signal for clustering/banding is greatest in latest CAM and ensemble guidance.

...Central Plains to the Upper MS Valley...
Low-level warm air advection will likely become increasingly focused
through the day and into the overnight hours from the central Plains
into the upper MS Valley. 850 mb winds are forecast to strengthen to
40-50 knots by this evening and will support steady moistening in
the lowest 1-2 km under a plume of 7-7.5 C/km mid-level lapse rates.
Forecast soundings suggest that this environment will be weakly
capped and should support isolated to scattered thunderstorms during
the afternoon hours across the central Plains before
spreading/re-developing northeastward into the upper MS Valley late
tonight. While deep-layer wind shear will not be overly strong
(around 30 knots), it should be sufficient for a few transient
organized cells capable of large hail.

A more conditional supercell threat may materialize across portions
of the lower MO valley where some CAM guidance depicts convection
developing late afternoon along the surface warm front. Forecast
soundings from this region suggest a weakly capped, but moderately
buoyant and strongly sheared environment may be in place that could
support a well-organized supercell. However, poor ensemble consensus
limits confidence in this scenario.

...Central to northern Rockies...
00z RAOBs from the Great Basin/Four Corners region sampled steep
mid-level lapse rates with modest mid-level moisture. While fairly
dry, this environment was sufficient for convection yesterday and
will likely support additional thunderstorms across the central to
northern Rockies this afternoon as diurnal heating erodes inhibition
and maximizes surface-based buoyancy. Ascent ahead of the decaying
upper wave will likely support isolated to scattered thunderstorms,
and a combination of modest deep-layer wind shear and deep,
well-mixed boundary layers will promote strong to severe downburst
winds. A fairly strong wind signal in latest HREF guidance
co-located with transient UH streaks lent enough confidence to
expand 5% wind probabilities northwestward to address this concern.

...CA Coast...
A progressive upper wave will move into northern CA late this
afternoon into the overnight hours. As this occurs, ascent within
the left-exit region of an attendant upper jet, coupled with cool
mid-level temperatures near the center of the upper low, should
support isolated thunderstorms across northern CA. Winds within the
lowest 1-2 km should increase to around 40 knots as the wave moves
onshore, which may be augmented by convective downdrafts to yield a
few damaging gusts along the coast.

..Moore/Halbert.. 04/11/2026

$$

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ACUS01 KWNS 111244
SWODY1
SPC AC 111242

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0742 AM CDT Sat Apr 11 2026

Valid 111300Z - 121200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE
SOUTHERN HIGH PLAINS...

...SUMMARY...
Scattered thunderstorms producing hail and strong wind gusts are
possible across portions of the southern High Plains this afternoon
and evening. More isolated strong to severe thunderstorms are
expected across parts of the central Rockies, central Plains, upper
Mississippi Valley, and portions of the California coast.

...Southern High Plains...
Thunderstorm development is likely by mid/late-afternoon across
southwest Texas and eastern New Mexico as increase forcing for
ascent overspreads modest but increasing low-level moisture.
Initially discrete cells are likely and will pose a threat for large
hail given adequate deep-layer wind shear /generally 30-40 kt/.
However, weak capping and strong ascent should promote upscale
growth by early evening into several linear clusters. As this
transition occurs, strong to severe wind gust potential will
increase and become the predominant hazard, though an embedded
circulation or two may occur with a tornado possible.

...Central Plains to the Upper Mississippi Valley...
Low-level warm air advection will likely become increasingly focused
through the day and into the overnight hours from the central Plains
into the upper Mississippi Valley. 850 mb winds are forecast to
steadily strengthen to 40-60 kt by this evening and will support
moistening in the lowest 1-2 km under a plume of 7-7.5 C/km
mid-level lapse rates. Forecast soundings suggest that this
environment will be weakly capped and should support isolated to
widely scattered thunderstorms during the afternoon hours across the
central Plains before spreading/re-developing northeastward into the
upper Mississippi Valley late tonight. While deep-layer wind shear
will not be overly strong (around 30 kt), it should be sufficient
for a few organized cells capable of severe hail.

A more conditional supercell potential may materialize by mid/late
afternoon through early evening across portions of the middle/lower
Missouri Valley near/just south of the northward-shifting surface
warm front, which may augmented by residual cloud cover/weakening
storms across northeast Kansas/far southeast Nebraska in the
pre-dawn hours. Forecast soundings from this region suggest a weakly
capped, but moderately buoyant airmass, with notably strong low-level/deep-layer wind profiles that would conditionally support
supercells including some tornado risk.

...Central/northern Rockies...
A northeast-ejecting shortwave trough, along with steep mid-level
lapse rates and modest mid-level moisture, will likely support
additional thunderstorms across the central to northern Rockies this
afternoon as diurnal heating occurs. A combination of modest
deep-layer wind shear and well-mixed boundary layers will support
potential for strong to severe downburst winds.

...Northern/central California Coast...
A progressive upper wave will continue eastward and reach the
northern California coast tonight. As this occurs, ascent within
the left-exit region of an attendant upper jet, coupled with cool
mid-level temperatures near the center of the upper low, will
support isolated thunderstorms across northern/central California.
Winds within the lowest 1-2 km AGL should increase to around 40 kt
as the wave moves onshore, which will contribute to the potential
for convective downdrafts to produce a few locally damaging wind
gusts.

..Guyer/Broyles.. 04/11/2026

$$

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ACUS01 KWNS 111629
SWODY1
SPC AC 111628

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1128 AM CDT Sat Apr 11 2026

Valid 111300Z - 121200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE
SOUTHERN HIGH PLAINS...

...SUMMARY...
Scattered thunderstorms producing hail and strong wind gusts are
possible across portions of the southern High Plains this afternoon
and evening. More isolated strong to severe thunderstorms are
expected across parts of the central Rockies, central Plains, upper
Mississippi Valley, and portions of the California coast.

...Synopsis...
Recent satellite imagery reveals two shortwave troughs, one moving
through the Great Basin and the other moving into central Mexico,
progressing through the southwesterly flow aloft between the
subtropical ridging that extends through the Southeast states and a
deep upper low off the central West Coast. Steep mid-level lapse
rates precede the northern shortwave (i.e. from the northern/central
Rockies northeastward) and low-level moisture continues to advect
northward across the southern and central Plains. Both of these
factors will increase buoyancy ahead of these two shortwaves, which
are expected to become increasingly phased as they progress
northeastward throughout the day. This evolution will support a
large area of thunderstorms from the northern Rockies through the
southern Plains this afternoon/evening. Environmental conditions
support strong to isolated severe thunderstorms across these areas,
with a relatively higher chance of severe from the southern High
Plains into central TX and along the eastern NE/KS border vicinity.

Additionally, the West Coast upper low is forecast to progress east-southeastward into southern OR and northern/central CA this
evening and overnight, supporting the potential for thunderstorms, a
few of which could be strong.

...Southern High Plains into Central Texas...
Scattered to numerous thunderstorms are expected to develop this
afternoon across the southern High Plains as a shortwave trough
lifts out of central Mexico and interacts with the moist and
modestly buoyant airmass in places over the region. A few initially
discrete storms are possible, and adequate deep-layer wind shear
around 35 kt could result in a few instances of severe hail.
However, weak capping and strong ascent should promote increasing
thunderstorm coverage, resulting in a transition to a more clustered
storm mode. Eventual evolution into one or more line segments is
possible, particularly over southwest TX as low-level flow
nocturnally strengthens and low-level moisture increases. As this
transition occurs, damaging gust potential will become the
predominant hazard. The strengthening low-level flow will also
lengthen low-level hodograph, supporting the potential for an
embedded circulation or two, particularly along the southern extent
of whatever line develops.

...Central Plains into the Upper Mississippi Valley...
Recent surface analysis places a warm front across central KS. This
warm front is forecast to progress northward throughout the day amid
persistent southerly flow and resulting moderate/strong low-level
moisture advection. Given the ongoing cloud cover across the region,
as well as the showers and thunderstorms over northwest MO, there is
some uncertainty to how this surface boundary will evolve. General
expectation is for this front to extend from the central NE vicinity
into north-central MO by this evening.

Large, looping low-level hodographs are anticipated in the vicinity
of this warm front. These profiles, along with dewpoints in the
low/mid 60s and modestly steep mid-level lapse rates, result in an
environment that is conditionally favorable for supercells. However,
some capping will likely linger across the region and large-scale
forcing will be negligible, casting doubt to whether convective
initiation will be realized. This uncertainty is matched by the CAM
guidance, none of which establishes meaningful convection during the
afternoon and evening. All that to say, if an updraft does mature in
this environment, all severe hazards are possible, including a
tornado.

More certain (but less intense) thunderstorm potential is
anticipated as low-level warm air advection becomes increasingly
focused from the central Plains into the upper Mississippi Valley
this evening and overnight. Moderate elevated buoyancy and
deep-layer shear support the potential for a few stronger updrafts
capable of hail as thunderstorms expand northeastward from IA into
the Upper Midwest.

...Northern/Central Rockies...
Scattered thunderstorm development is anticipated across the
northern and central Rockies, ahead of a shortwave trough
progressing northeastward into the region. Deep boundary-layer
mixing ahead of this system coupled with steep mid-level lapse rates
and moderate deep-layer vertical shear will result in an environment
that supports the potential for strong to severe gusts across much
of the region.

...Northern/Central California Coast...
A frontal band, associated with an upper low moving over the
northern California coast tonight, is expected to progress
southeastward through the central CA coastal vicinity this evening. Thermodynamic profiles appear marginally supportive of isolated
convection deep enough to produce lightning. Winds within the lowest
1-2 km AGL should increase to around 40 kt as the wave moves
onshore, which will contribute to the potential for convective
downdrafts to produce a few locally damaging wind gusts.

..Mosier/Squitieri.. 04/11/2026

$$

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ACUS01 KWNS 111707
SWODY1
SPC AC 111705

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1205 PM CDT Sat Apr 11 2026

Valid 111630Z - 121200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE
SOUTHERN HIGH PLAINS...

...SUMMARY...
Scattered thunderstorms producing hail and strong wind gusts are
possible across portions of the southern High Plains this afternoon
and evening. More isolated strong to severe thunderstorms are
expected across parts of the central Rockies, central Plains, upper
Mississippi Valley, and portions of the California coast.

...Synopsis...
Recent satellite imagery reveals two shortwave troughs, one moving
through the Great Basin and the other moving into central Mexico,
progressing through the southwesterly flow aloft between the
subtropical ridging that extends through the Southeast states and a
deep upper low off the central West Coast. Steep mid-level lapse
rates precede the northern shortwave (i.e. from the northern/central
Rockies northeastward) and low-level moisture continues to advect
northward across the southern and central Plains. Both of these
factors will increase buoyancy ahead of these two shortwaves, which
are expected to become increasingly phased as they progress
northeastward throughout the day. This evolution will support a
large area of thunderstorms from the northern Rockies through the
southern Plains this afternoon/evening. Environmental conditions
support strong to isolated severe thunderstorms across these areas,
with a relatively higher chance of severe from the southern High
Plains into central TX and along the eastern NE/KS border vicinity.

Additionally, the West Coast upper low is forecast to progress east-southeastward into southern OR and northern/central CA this
evening and overnight, supporting the potential for thunderstorms, a
few of which could be strong.

...Southern High Plains into Central Texas...
Scattered to numerous thunderstorms are expected to develop this
afternoon across the southern High Plains as a shortwave trough
lifts out of central Mexico and interacts with the moist and
modestly buoyant airmass in places over the region. A few initially
discrete storms are possible, and adequate deep-layer wind shear
around 35 kt could result in a few instances of severe hail.
However, weak capping and strong ascent should promote increasing
thunderstorm coverage, resulting in a transition to a more clustered
storm mode. Eventual evolution into one or more line segments is
possible, particularly over southwest TX as low-level flow
nocturnally strengthens and low-level moisture increases. As this
transition occurs, damaging gust potential will become the
predominant hazard. The strengthening low-level flow will also
lengthen low-level hodograph, supporting the potential for an
embedded circulation or two, particularly along the southern extent
of whatever line develops.

...Central Plains into the Upper Mississippi Valley...
Recent surface analysis places a warm front across central KS. This
warm front is forecast to progress northward throughout the day amid
persistent southerly flow and resulting moderate/strong low-level
moisture advection. Given the ongoing cloud cover across the region,
as well as the showers and thunderstorms over northwest MO, there is
some uncertainty to how this surface boundary will evolve. General
expectation is for this front to extend from the central NE vicinity
into north-central MO by this evening.

Large, looping low-level hodographs are anticipated in the vicinity
of this warm front. These profiles, along with dewpoints in the
low/mid 60s and modestly steep mid-level lapse rates, result in an
environment that is conditionally favorable for supercells. However,
some capping will likely linger across the region and large-scale
forcing will be negligible, casting doubt to whether convective
initiation will be realized. This uncertainty is matched by the CAM
guidance, none of which establishes meaningful convection during the
afternoon and evening. All that to say, if an updraft does mature in
this environment, all severe hazards are possible, including a
tornado.

More certain (but less intense) thunderstorm potential is
anticipated as low-level warm air advection becomes increasingly
focused from the central Plains into the upper Mississippi Valley
this evening and overnight. Moderate elevated buoyancy and
deep-layer shear support the potential for a few stronger updrafts
capable of hail as thunderstorms expand northeastward from IA into
the Upper Midwest.

...Northern/Central Rockies...
Scattered thunderstorm development is anticipated across the
northern and central Rockies, ahead of a shortwave trough
progressing northeastward into the region. Deep boundary-layer
mixing ahead of this system coupled with steep mid-level lapse rates
and moderate deep-layer vertical shear will result in an environment
that supports the potential for strong to severe gusts across much
of the region.

...Northern/Central California Coast...
A frontal band, associated with an upper low moving over the
northern California coast tonight, is expected to progress
southeastward through the central CA coastal vicinity this evening. Thermodynamic profiles appear marginally supportive of isolated
convection deep enough to produce lightning. Winds within the lowest
1-2 km AGL should increase to around 40 kt as the wave moves
onshore, which will contribute to the potential for convective
downdrafts to produce a few locally damaging wind gusts.

..Mosier/Squitieri.. 04/11/2026

$$

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ACUS01 KWNS 112001
SWODY1
SPC AC 112000

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0300 PM CDT Sat Apr 11 2026

Valid 112000Z - 121200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF NORTH-CENTRAL KANSAS AND SOUTHEASTERN NEBRASKA...

...SUMMARY...
Scattered thunderstorms producing hail and strong wind gusts are
possible across portions of the southern High Plains and into parts
of Kansas and Nebraska this afternoon and evening. More isolated
strong to severe thunderstorms are expected across parts of the
central Rockies, upper Mississippi Valley, and portions of the
California coast.

...20z Update KS/NE...
An MCV evident in visible imagery over southwest/central KS is
forecast to shift northeastward this afternoon toward a differential
heating zone associated with a modifying remnant outflow boundary
across northern KS and southern NE. Ample heating south of this zone
has warmed temperatures ~5-7 degree above model guidance, with
observation trends suggestive of locally stronger buoyancy and
vertical shear on modified 12 and 18z RAOBs (1500-2000 J/kg of
MLCAPE). While overall mid-level flow is modest, some enhancement in
the low and mid-levels ahead of the MCV is also evident in area
VADs, bolstering bulk shear to 30-35 kt. Backed low-level winds
along the retreating boundary are also aiding in maintaining sizable
clockwise curved low-level hodographs. This could support the
development of small supercell structures with potential to produce
tornadoes, particularly near and just north of the retreating
outflow boundary, and perhaps in close proximity to the MCV.

Otherwise, some hail and localized strong wind gusts are possible
with any more robust storms able to develop and maintain themselves
into this evening. Deep-layer shear is progged to increase after
dark, as a 40-50 kt low-level jet develops, supporting an increase
in storm coverage along and north of the boundary tonight. Hail and
damaging winds would be the primary threats. Given the local
increase in severe potential, a small zone ahead of the MCV and
along the boundary has been upgraded to a level 2/5 Slight Risk.

...TX and NM...
Scattered strong to severe thunderstorms remain likely tonight
across West TX, the Rio Grand Valley and southeastern NM.
Eventually, one ore more lines or clusters may emerge and spread
east/northeast into central TX/west-central OK. A risk for damaging
gusts or a tornado remain possible with these storms into early
Sunday morning. High-res guidance suggests these storms may maintain
intensity slightly farther east. The 5% wind are was moved eastward
to account for the overnight/early morning risk for a few damaging
gusts.

Elsewhere, severe storms remain possible over parts of the Rockies
and West Coast. The outlook remains largely unchanged. See the prior
discussion for additional information.

..Lyons.. 04/11/2026

.PREV DISCUSSION... /ISSUED 1205 PM CDT Sat Apr 11 2026/

...Synopsis...
Recent satellite imagery reveals two shortwave troughs, one moving
through the Great Basin and the other moving into central Mexico,
progressing through the southwesterly flow aloft between the
subtropical ridging that extends through the Southeast states and a
deep upper low off the central West Coast. Steep mid-level lapse
rates precede the northern shortwave (i.e. from the northern/central
Rockies northeastward) and low-level moisture continues to advect
northward across the southern and central Plains. Both of these
factors will increase buoyancy ahead of these two shortwaves, which
are expected to become increasingly phased as they progress
northeastward throughout the day. This evolution will support a
large area of thunderstorms from the northern Rockies through the
southern Plains this afternoon/evening. Environmental conditions
support strong to isolated severe thunderstorms across these areas,
with a relatively higher chance of severe from the southern High
Plains into central TX and along the eastern NE/KS border vicinity.

Additionally, the West Coast upper low is forecast to progress east-southeastward into southern OR and northern/central CA this
evening and overnight, supporting the potential for thunderstorms, a
few of which could be strong.

...Southern High Plains into Central Texas...
Scattered to numerous thunderstorms are expected to develop this
afternoon across the southern High Plains as a shortwave trough
lifts out of central Mexico and interacts with the moist and
modestly buoyant airmass in places over the region. A few initially
discrete storms are possible, and adequate deep-layer wind shear
around 35 kt could result in a few instances of severe hail.
However, weak capping and strong ascent should promote increasing
thunderstorm coverage, resulting in a transition to a more clustered
storm mode. Eventual evolution into one or more line segments is
possible, particularly over southwest TX as low-level flow
nocturnally strengthens and low-level moisture increases. As this
transition occurs, damaging gust potential will become the
predominant hazard. The strengthening low-level flow will also
lengthen low-level hodograph, supporting the potential for an
embedded circulation or two, particularly along the southern extent
of whatever line develops.

...Central Plains into the Upper Mississippi Valley...
Recent surface analysis places a warm front across central KS. This
warm front is forecast to progress northward throughout the day amid
persistent southerly flow and resulting moderate/strong low-level
moisture advection. Given the ongoing cloud cover across the region,
as well as the showers and thunderstorms over northwest MO, there is
some uncertainty to how this surface boundary will evolve. General
expectation is for this front to extend from the central NE vicinity
into north-central MO by this evening.

Large, looping low-level hodographs are anticipated in the vicinity
of this warm front. These profiles, along with dewpoints in the
low/mid 60s and modestly steep mid-level lapse rates, result in an
environment that is conditionally favorable for supercells. However,
some capping will likely linger across the region and large-scale
forcing will be negligible, casting doubt to whether convective
initiation will be realized. This uncertainty is matched by the CAM
guidance, none of which establishes meaningful convection during the
afternoon and evening. All that to say, if an updraft does mature in
this environment, all severe hazards are possible, including a
tornado.

More certain (but less intense) thunderstorm potential is
anticipated as low-level warm air advection becomes increasingly
focused from the central Plains into the upper Mississippi Valley
this evening and overnight. Moderate elevated buoyancy and
deep-layer shear support the potential for a few stronger updrafts
capable of hail as thunderstorms expand northeastward from IA into
the Upper Midwest.

...Northern/Central Rockies...
Scattered thunderstorm development is anticipated across the
northern and central Rockies, ahead of a shortwave trough
progressing northeastward into the region. Deep boundary-layer
mixing ahead of this system coupled with steep mid-level lapse rates
and moderate deep-layer vertical shear will result in an environment
that supports the potential for strong to severe gusts across much
of the region.

...Northern/Central California Coast...
A frontal band, associated with an upper low moving over the
northern California coast tonight, is expected to progress
southeastward through the central CA coastal vicinity this evening. Thermodynamic profiles appear marginally supportive of isolated
convection deep enough to produce lightning. Winds within the lowest
1-2 km AGL should increase to around 40 kt as the wave moves
onshore, which will contribute to the potential for convective
downdrafts to produce a few locally damaging wind gusts.

$$

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ACUS01 KWNS 120058
SWODY1
SPC AC 120056

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0756 PM CDT Sat Apr 11 2026

Valid 120100Z - 121200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS SOUTHERN TEXAS...

...SUMMARY...
Scattered strong to severe thunderstorms remain possible overnight
across portions central Texas while more isolated severe
thunderstorms are expected across the southern and central Plains
and into the upper Mississippi River Valley.

...Synopsis...
Strong to severe thunderstorms remain possible late this evening and
into the overnight hours across parts of the central CONUS. A lee
cyclone will continue to deepen across the northern High Plains and
maintain northward moisture return across the Plains as well as a
focused zone of strong isentropic ascent across the upper MS Valley.
Buoyant conditions and modest, but adequate, deep-layer wind shear
should continue to support the potential for organized convection.

...Texas...
The early stages of MCV development are noted in regional
reflectivity across the Big Bend region of TX where a convective
clustering has been focused over the past several hours. The nearby
00z DRT RAOB recently sampled a 0-6 km bulk shear value on the order
of 45 knots, which is favorable for organized convection. This
kinematic environment remains favorable for organized convection and
could support intensification/organization of a convective line
associated with the MCV as it migrates eastward into a more
moist/buoyant environment. This scenario is supported by recent CAM
guidance, and warrants maintaining/expanding 15% wind probabilities
downstream of the MCV.

...Oklahoma into Kansas...
Modestly moist and uncapped conditions were recently sampled across
northern TX and central OK with effective bulk shear values on the
order of 25 knots. Continued northward moisture advection should
modulate nocturnal stabilization, and increasing ascent ahead of the
upper wave emanating out of northern Mexico may support isolated
strong to severe convection through the late evening and overnight
hours.

...Upper MS Valley...
VWPs across the Midwest and upper MS Valley all show a strong
veering within the lowest 1-2 km and a recent uptick in wind speed
within this layer. Additionally, upstream RAOBs sampled 7-8 C/km
lapse rates that should be advecting eastward into the region
through the overnight hours. The combination of continued ascent and
increasing instability should promote the potential for additional
elevated convection late tonight with an attendant threat for hail
approach severe limits.

...California...
The 00z OAK RAOB sampled weak buoyancy with around 150 J/kg SBCAPE.
However, temperatures near 700 mb should continue to cool through
the overnight hours with the approach of an upper wave just off the
coast. Continued ascent within the left-exit region of the attendant
upper jet will maintain the potential for isolated convection along
the CA coast and areas inland. Additionally, 35-45 knot flow within
the lowest few kilometers will likely be maintained through the
overnight. Given the expectation of a slight increase in buoyancy
and maintenance of low-level flow, opted to keep the 5% wind risk.

..Moore.. 04/12/2026

$$

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ACUS01 KWNS 120603
SWODY1
SPC AC 120601

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0101 AM CDT Sun Apr 12 2026

Valid 121200Z - 131200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PORTIONS OF
CENTRAL AND SOUTHERN TEXAS...

...SUMMARY...
Isolated to scattered severe thunderstorms are possible this
afternoon and evening across parts of the southern High Plains. More
isolated severe storms will be possible across portions of the Upper
Great Lakes and northern Rockies.

...Synopsis...
Early-morning surface observations reveal a surface low developing
across the northern High Plains with a broad fetch of southerly flow
from the western Gulf into the Plains and Midwest. This broad warm
sector characterized by mid 50s to low/mid 60s dewpoints will
largely remain in place through the day as the surface low
translates east across the Plains into the Great Lakes region
tonight. The greatest potential for strong/severe thunderstorms will
reside within this warm sector where regional forcing for ascent
will support a chance for deep convection.

...Southern Plains...
Latest 00z HREF/REFS guidance, as well as more recent CAM solutions,
all show considerable variability in the evolution of an ongoing MCS
through late morning across southern/southeast TX. While most
solutions depict a steady weakening trend, others - notably the
WRF-ARW - hint at some continued wind threat across the TX Coastal
Plain this morning. Regardless, this activity is forecast to
diminish by late morning/early afternoon, and will likely leave an
outflow boundary on the western periphery of the cold pool in its
wake.

Dewpoints in the low to mid 60s will quickly return northward in the
wake of the MCS with ensemble guidance depicting a plume of MLCAPE
values between 1500-2000 J/kg from central TX into western OK by
mid-afternoon. Thunderstorm development appears possible along any
residual outflow boundaries across central TX given weak capping
depicted in forecast soundings, though confidence in precisely where
this will occur or how widespread storm coverage will be remains
fairly uncertain. Thunderstorm initiation off the Sierra Del Carmen
mountains in northern Mexico and along a weak dryline across
southern KS southward into western OK/TX appears more probable,
though again, storm coverage will likely remain fairly isolated
given weak forcing for ascent and some degree of synoptic-scale
subsidence in the wake of the upper disturbance currently passing
over the region.

Convection that can develop within this buoyant and weakly capped
environment could become fairly intense given favorable
thermodynamic profiles. Despite some mid-level backing in forecast
hodographs, effective bulk shear values appear sufficient for a
large, to perhaps very large hail threat. However, given the
aforementioned uncertainties in thunderstorm coverage, 15% hail
probabilities have been confined to where ensemble guidance depicts
the best overall convective signal.

...Minnesota...
A lee cyclone evident in recent surface observations over the
northern High Plains will migrate eastward along the U.S./Canaidan
border through the day, reaching northern MN by around peak heating.
A narrow tongue of returning moisture may support a corridor of
sufficient ascent and buoyancy for deep convection. While latest
guidance remains somewhat mixed on thunderstorm coverage, forecast
soundings suggest elevated convection may support a threat for large
hail. Furthermore, several high-res forecast soundings depict an
environment favorable for surface-based supercells along the frontal
zone where dewpoints may reach into the mid/upper 50s. While this
potential appears very low per recent ensemble guidance, some
tornado threat could materialize along the front where STP values of
1-2 may emerge.

...Northern Rockies...
A plume of mid-level moisture (PWATs between 0.4 to 0.5 inches) was
recently observed in regional 00z RAOBs across the Great Basin
region. This air mass will largely remain in place over the next 24
hours ahead of an approaching upper low out of northern CA. This
mid-level moisture will support another day of fairly modest
surface-based buoyancy (around 250-500 J/kg SBCAPE), but persistent
30-40 knot flow within the CAPE-bearing layer combined with somewhat
deep boundary-layer mixing (LCLs forecast to be around 2 km) may
support another day of strong to severe downburst winds with the
more robust convective cells.

..Moore/Halbert.. 04/12/2026

$$

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ACUS01 KWNS 121256
SWODY1
SPC AC 121254

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0754 AM CDT Sun Apr 12 2026

Valid 121300Z - 131200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
TEXAS...

...SUMMARY...
Isolated to scattered severe thunderstorms are possible today into
evening mainly across parts of Texas and perhaps other nearby parts
of the southern Plains. More isolated severe storms may occur across
portions of the Upper Great Lakes and northern Rockies.

...Texas/Southern Plains...
A rather complex scenario exists early today attributable to several
factors including an MCS that de-intensified/decayed generally near
I-35 in Texas overnight, with residual cloud cover and outflow
impacts. Potentially focused in vicinity of outflow, the passing
mid-level wave and persistent warm/moist advection may support storm persistence and redevelopment/intensification later today across
central Texas into parts of east Texas and possibly Louisiana within
a moderately unstable environment.

In the wake of the mid-level wave, mid-level height rises/subsidence
are otherwise anticipated coincident with the dryline from central
Kansas south-southwestward across western Oklahoma and
west/southwest Texas. The extent and likelihood of storm development
later today is highly uncertain, but if/where storms do form, the
environment would generally be supportive of supercells and related
hazards given ample buoyancy and moderate deep-layer shear.

...Minnesota/Wisconsin...
A surface low over the northern Plains will migrate eastward along
the U.S./Canadian border through the day, reaching northern
Minnesota by around peak heating. A narrow tongue of returning
moisture may support a corridor of sufficient ascent and buoyancy
for deep convection. A few surface-based supercells could occur
along the frontal zone where dewpoints may reach into the mid/upper
50s F. While this potential appears low/uncertain per latest
guidance, some tornado threat could materialize along the front.
Hail/wind will otherwise be possible regionally on an isolated
basis.

...Northern Rockies...
Ahead of an approaching upper wave, mid-level moisture will support
another day of fairly modest surface-based buoyancy with persistent
30-40 knot flow within the CAPE-bearing layer. Combined with
somewhat deep boundary-layer mixing, this may support strong to
severe downburst winds with the more robust convective cells, mainly
this afternoon through early evening.

..Guyer/Broyles.. 04/12/2026

$$

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ACUS01 KWNS 121630
SWODY1
SPC AC 121629

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1129 AM CDT Sun Apr 12 2026

Valid 121630Z - 131200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
SOUTHWEST AND CENTRAL TX...

...SUMMARY...
Isolated to scattered severe thunderstorms are possible today into
evening mainly across parts of Texas and perhaps other nearby parts
of the southern Plains. More isolated severe storms may occur across
portions of the Upper Great Lakes and northern Rockies.

...Synopsis...
Recent satellite imagery shows a pair of phased shortwave troughs
over the Plains, one moving through the Dakotas and another moving
through KS/OK. Both of these waves are forecast to continue
northeastward through the day, with the northern wave reaching
northwestern Ontario and the southern wave reaching the Great Lakes
region. This evolution will take these waves east/northeast of the
higher low-level moisture, which will remain in a corridor from the
southern Plains northeastward into the Upper Midwest. Showers and
thunderstorms are anticipated throughout much of this corridor
today, with highest thunderstorm chances across central/east TX and
from the Upper Midwest into the Great Lakes.

Farther west, an upper low is slowly drifting eastward across
northern CA. Guidance suggests this eastward drift will continue
today, with several shortwave troughs rotating quickly through the
base of this system and ejecting across the Great Basin and northern
Rockies. Large-scale ascent and modest mid-level moisture associated
with these waves will combine with cold temperatures aloft and
associated buoyancy to support thunderstorms today from northern CA
across the northern Great Basin and northern Rockies, and into the
northern Plains.

...Southern/Central Plains...
Much of this region will be displaced south and west of any notable
large-scale forcing for ascent. This limited ascent, combined with
the showers and isolated thunderstorms currently ongoing across
central and east TX, complicates the overall forecast today, with
mesoscale factors likely contributing significantly to when and
where storms develop this afternoon and evening. General expectation
is for development along the southern and western periphery on the
ongoing storms (i.e. from southeast/south-central TX into southwest
TX) later this afternoon and this evening. This redevelopment will
be supported by a combination of moist advection, modest heating,
and limited low-level convergence. Moderate to strong buoyancy amid
moderate vertical shear could support supercells if the mode remains
discrete. However, the weakness in the mid-level flow suggests
storms may tend to cluster, a scenario that is supported by most CAM
guidance. Buoyancy and shear are still strong enough to support
rotating updrafts and large hail early in the convective cycle, but
the trends towards a messy convective mode could limit the
persistence and coverage of robust updrafts. Damaging gusts are
possible even with the clustered storm mode, especially given there
is some potential for slightly more organized bowing segments over
time.

Farther west, mid-level height rises/subsidence are anticipated
coincident with the dryline from central Kansas south-southwestward
across western Oklahoma and west/southwest Texas. The environment, characterized by 1500 to 2000 J/kg of MLCAPE and 30 to 40 kt of
westerly deep-layer shear, is conditionally supportive of supercells
capable of all severe hazards. However, the previously mentioned
height rises and subsidence, combined with modest convective
inhibition, are generally expected to preclude thunderstorm
development. Even so, given the conditional risk, Marginal risk
probabilities will be maintained.

...Minnesota/Wisconsin...
Recent surface analysis places a low just west of FAR, with a warm
front extending southwestward across central/southeast MN and
southern WI. This low is forecast to move eastward today, while the
warm front expands northward. A narrow corridor of surface-based
buoyancy could develop from north-central MN into far northwest WI
as dewpoints increase in the upper 50s (perhaps even low 60s).
Thunderstorm initiation appears possible along the cold front within
this corridor, although veered low-level flow and northward/westward displacement of the better forcing casts doubt to whether updrafts
will be maintained. Any storms that do mature within this warm
sector should become supercells capable of all severe hazards,
including large hail and tornadoes. However, low confidence in storm development and maturity precludes higher probabilities with this
outlook.

...Northern Rockies...
Mid-level moisture will support another day of modest surface-based
buoyancy ahead of the shortwave trough mentioned in the synopsis.
Persistent 30-40 knot flow within the CAPE-bearing layer combined
with somewhat deep boundary-layer mixing will support strong to
severe downburst winds with the more robust convective cells, mainly
this afternoon through early evening.

..Mosier/Squitieri.. 04/12/2026

$$

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ACUS01 KWNS 121958
SWODY1
SPC AC 121956

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0256 PM CDT Sun Apr 12 2026

Valid 122000Z - 131200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
CENTRAL TEXAS...

...SUMMARY...
Isolated to scattered severe thunderstorms remain possible today
into evening mainly across parts of Texas and perhaps other nearby
parts of the southern Plains. More isolated severe storms may occur
across portions of the Upper Great Lakes and northern Rockies.

...20z Update Central TX...
Filtered diurnal heating in the wake of earlier showers and storms
across much of central TX was supporting moderate destabilization
this afternoon. While mid-level lapse rates are generally poor,
sufficient destabilization should support a gradual uptick in
convective coverage this afternoon and evening. With moderate
deep-layer shear in place, some organization could support a risk
for damaging gusts, hail, and tornado or two.

...MN/WI...
The aforementioned warm front continues to surge north but has
slowed farther south than earlier guidance. Weak to moderate
destabilization along and just south of the boundary will remain
supportive of a conditions supercell risk this afternoon/evening.
Strong shear profiles east of the surface low and near the rapidly
modifying boundary could support a risk for hail and possibly a
tornado. Have shifted severe probabilities southward slightly to
better match the observed frontal positioning. See MCD #390 for the
latest information.

...OK/KS/TX Panhandle...
A conditional risk for a supercell or two remains evident this
afternoon across the dryline in the central and southern Plains.
Ample heating in the wake of an early morning MCS could allow for
isolated storm this afternoon or evening as the dryline is forecast
to mix eastward before eventually retreating. Forecast guidance
continues to show weak subsidence suppressing convective
development, but deepening cumulus evident over the southern TX
Panhandle could support an isolated storm this evening. All severe
hazards would be possible.

...Intermountain West...
Steep mid-level lapse rates beneath the cold core of the upper low
over the West will continue to support scattered high-based storms
this afternoon. With a relatively dry-sub cloud layer, somewhat deep boundary-layer mixing will support strong to
severe downburst winds.

..Lyons.. 04/12/2026

.PREV DISCUSSION... /ISSUED 1129 AM CDT Sun Apr 12 2026/

...Synopsis...
Recent satellite imagery shows a pair of phased shortwave troughs
over the Plains, one moving through the Dakotas and another moving
through KS/OK. Both of these waves are forecast to continue
northeastward through the day, with the northern wave reaching
northwestern Ontario and the southern wave reaching the Great Lakes
region. This evolution will take these waves east/northeast of the
higher low-level moisture, which will remain in a corridor from the
southern Plains northeastward into the Upper Midwest. Showers and
thunderstorms are anticipated throughout much of this corridor
today, with highest thunderstorm chances across central/east TX and
from the Upper Midwest into the Great Lakes.

Farther west, an upper low is slowly drifting eastward across
northern CA. Guidance suggests this eastward drift will continue
today, with several shortwave troughs rotating quickly through the
base of this system and ejecting across the Great Basin and northern
Rockies. Large-scale ascent and modest mid-level moisture associated
with these waves will combine with cold temperatures aloft and
associated buoyancy to support thunderstorms today from northern CA
across the northern Great Basin and northern Rockies, and into the
northern Plains.

...Southern/Central Plains...
Much of this region will be displaced south and west of any notable
large-scale forcing for ascent. This limited ascent, combined with
the showers and isolated thunderstorms currently ongoing across
central and east TX, complicates the overall forecast today, with
mesoscale factors likely contributing significantly to when and
where storms develop this afternoon and evening. General expectation
is for development along the southern and western periphery on the
ongoing storms (i.e. from southeast/south-central TX into southwest
TX) later this afternoon and this evening. This redevelopment will
be supported by a combination of moist advection, modest heating,
and limited low-level convergence. Moderate to strong buoyancy amid
moderate vertical shear could support supercells if the mode remains
discrete. However, the weakness in the mid-level flow suggests
storms may tend to cluster, a scenario that is supported by most CAM
guidance. Buoyancy and shear are still strong enough to support
rotating updrafts and large hail early in the convective cycle, but
the trends towards a messy convective mode could limit the
persistence and coverage of robust updrafts. Damaging gusts are
possible even with the clustered storm mode, especially given there
is some potential for slightly more organized bowing segments over
time.

Farther west, mid-level height rises/subsidence are anticipated
coincident with the dryline from central Kansas south-southwestward
across western Oklahoma and west/southwest Texas. The environment, characterized by 1500 to 2000 J/kg of MLCAPE and 30 to 40 kt of
westerly deep-layer shear, is conditionally supportive of supercells
capable of all severe hazards. However, the previously mentioned
height rises and subsidence, combined with modest convective
inhibition, are generally expected to preclude thunderstorm
development. Even so, given the conditional risk, Marginal risk
probabilities will be maintained.

...Minnesota/Wisconsin...
Recent surface analysis places a low just west of FAR, with a warm
front extending southwestward across central/southeast MN and
southern WI. This low is forecast to move eastward today, while the
warm front expands northward. A narrow corridor of surface-based
buoyancy could develop from north-central MN into far northwest WI
as dewpoints increase in the upper 50s (perhaps even low 60s).
Thunderstorm initiation appears possible along the cold front within
this corridor, although veered low-level flow and northward/westward displacement of the better forcing casts doubt to whether updrafts
will be maintained. Any storms that do mature within this warm
sector should become supercells capable of all severe hazards,
including large hail and tornadoes. However, low confidence in storm development and maturity precludes higher probabilities with this
outlook.

...Northern Rockies...
Mid-level moisture will support another day of modest surface-based
buoyancy ahead of the shortwave trough mentioned in the synopsis.
Persistent 30-40 knot flow within the CAPE-bearing layer combined
with somewhat deep boundary-layer mixing will support strong to
severe downburst winds with the more robust convective cells, mainly
this afternoon through early evening.

$$

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ACUS01 KWNS 130051
SWODY1
SPC AC 130049

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0749 PM CDT Sun Apr 12 2026

Valid 130100Z - 131200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PORTIONS OF
CENTRAL TEXAS...

...SUMMARY...
Isolated to scattered severe thunderstorms remain possible this
evening across portions of central Texas and perhaps central/western
Oklahoma.

...Synopsis...
Mid-evening surface observations reveal an expansive warm sector
from the TX coast northward into the Plains and upper MS Valley.
Despite a high-quality thermodynamic environment throughout much of
this warm sector, a combination of residual capping across the upper
MS Valley and/or very weak ascent in the wake of an upper-level
disturbance is limiting the overall potential for thunderstorms
outside of the southern Plains. Across the West, convective coverage
is gradually diminishing and will continue to dwindle heading into
the late evening hours as nocturnal cooling begins to increase
inhibition.

...Southern Plains...
The most intense convection currently resides to the west of the
I-35 corridor in central TX where strong to severe thunderstorms
have developed on the western fringe of an expanding cold pool.
MLCAPE values to the west of the cold pool were recently sampled
near 2500 J/kg by the DRT and OUN soundings with around 30-35 knots
of effective bulk shear also noted. This environment is favorable
for organized convection, including splitting supercells with some
potential for large to very large hail. However, close proximity to
the residual cold pool should limit the overall spatial extent of
this threat, and most guidance depicts this activity waning later
tonight in the absence of persistent forcing for ascent.

Further north into western Oklahoma and northwest TX, continued
cumulus development along a diffuse dryline is noted in GOES
imagery. While storm development appears unlikely given the
approaching onset of nocturnal cooling, the downstream environment
remains highly favorable for intense convection per the 00z OUN
RAOB, and recent RRFS solutions hint at the potential for convection
within the next 1-3 hours (though these solutions appear to be
outliers compared to other guidance). Given this signal and the
favorable environment, opted to maintain 5% hail/wind probabilities
to account for this low-probability, but potentially high impact
scenario.

..Moore.. 04/13/2026

$$

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ACUS01 KWNS 130536
SWODY1
SPC AC 130534

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1234 AM CDT Mon Apr 13 2026

Valid 131200Z - 141200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE UPPER MISSISSIPPI RIVER VALLEY...

...SUMMARY...
Severe thunderstorms are likely across the Upper Mississippi Valley
and Great Lakes region with potential for large to very large hail,
damaging wind, and tornadoes. A more conditional and isolated risk
for severe storms is possible across portions of the southern Plains
late this afternoon and evening.

...Synopsis...
Early-morning water-vapor imagery depicts an upper trough with
multiple embedded vorticity maxima over the Great Basin. While the
primary upper wave will remain over the West for today, a leading
impulse is forecast to eject towards the northern Plains and into
the Great Lakes through tonight. At the surface, a weak lee cyclone
over the central High Plains will migrate northeastward in tandem
with the upper impulse, likely reaching the southern MN vicinity by
early evening. As this occurs, a plume of mid-60s dewpoints will
spread north into the upper MS Valley along and south of a warm
front. Scattered thunderstorm development along and north of the
warm front is anticipated by late afternoon as forcing for ascent
gradually increases. Elsewhere, more isolated strong to severe
thunderstorms are possible across portions of TX and OK where deep
mixing along a dryline may result in sustained deep convection.

...Upper MS Valley...
A combination of shortwave ridging and capping at the base of an EML
will limit thunderstorm development through much of the day across
southern MN into central WI. This will allow for continued moisture
return as a warm front lifts into the region with MLCAPE values
forecast to reach 2000-2500 J/kg by around 21 UTC. Thunderstorm
development will become increasingly probable through the 21-00 UTC
period as isentropic ascent strengthens ahead of the approaching
upper disturbance. Lingering inhibition coupled with 45-50 knot
effective bulk shear should promote initially discrete supercells
along or just north of the surface boundary. Hodograph elongation
appears favorable for a large hail threat, possibly as large as 2-3
inches with the more robust cells. Additionally, enhanced low-level
SRH along the frontal zone may result in a corridor of relatively
higher tornado potential if convection can remain rooted along the
boundary.

While the overall environment appears very favorable for intense
convection, east/northeasterly storm motions along or just north of
the warm front will likely promote storm advection towards the cool
side of the boundary and clustering/upscale growth through the
evening. This, combined with capping over the remainder of the warm
sector, limits confidence in a more widespread tornado threat, and
could modulate the potential for significant (2+ inch) hail within a
few hours after convective initiation. Nonetheless, a corridor of
higher hail potential remains evident in latest guidance along and
just north of the warm front where discrete supercells are most
probable. 30% hail probabilities have been shifted to reflect a
southward trend in frontal placement noted in most recent guidance.

...Southern Plains...
A moist and very unstable air mass will remain in place across TX
and OK today with MLCAPE values expected to increase to around 2500
J/kg by late afternoon. Ample diurnal heating/mixing on the western
periphery of the moisture plume will likely result in weak,
high-based convection by mid to late afternoon. Easterly storm
motions may promote downstream intensification as convection
migrates towards richer low-level moisture, but this will be
conditional on convection remaining sustained long enough to realize
the favorable thermodynamic environment. If this can occur,
deep-layer shear values on the order of 40 knots should promote
organized convection - likely in the form of supercells - with an
attendant threat for all hazards, including very large hail. While
both global and CAM ensemble guidance hint at this potential, the
lack of appreciable lifting mechanisms (aside from the dryline circulation/boundary-layer mixing) casts considerable uncertainty on
overall storm coverage.

..Moore/Wendt.. 04/13/2026

$$

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ACUS01 KWNS 131301
SWODY1
SPC AC 131300

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0800 AM CDT Mon Apr 13 2026

Valid 131300Z - 141200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHERN
MINNESOTA AND PARTS OF WISCONSIN...

...SUMMARY...
Severe thunderstorms are likely across the Upper Mississippi Valley
and Great Lakes region with potential for large to very large hail,
damaging wind, and tornadoes, mainly late this afternoon into
tonight. A more conditional and isolated risk for severe storms is
possible across portions of the southern Plains late this afternoon
and evening.

...Upper Mississippi Valley/Great Lakes including MN/WI...
Multiple lead mid-level disturbances over the northern High Plains
will progress northeastward today toward the Upper Midwest, with
strengthening winds aloft across this region particularly late today
and tonight. A surface low will tend to deepen/develop
east-northeastward from northeast Nebraska this morning into far
southern Minnesota and Wisconsin by tonight in vicinity of a slow-moving/stalled frontal boundary. Low/middle 60s F surface
dewpoints will advect north-northeastward and become increasingly
prevalent along/south of the aforementioned stationary/warm front
this afternoon. MLCAPE values are forecast to reach 2000-2500 J/kg
by around 21z/4pm CDT.

Thunderstorm development will become increasingly probable through
mid/late afternoon (21-00z) as isentropic ascent strengthens ahead
of the approaching upper disturbance. Lingering inhibition coupled
with 45-50 kt effective bulk shear should promote initially discrete
supercells along or just north of the surface boundary. Hodograph
elongation appears favorable for a large hail threat, possibly as
large as 2-3 inches in diameter with the more robust cells.
Additionally, enhanced low-level SRH along the frontal zone is
expected to result in a corridor of relatively higher tornado
potential for storms that can remain rooted immediately along the
boundary.

While the overall environment appears very favorable for intense convection/supercells, east-northeasterly storm motions along or
just north of the warm front will likely promote clustering/upscale
growth through the evening, with an increasing damaging wind
potential and a continued tornado risk via line-embedded circulation
potential.

...Northern Illinois/northern Indiana and southern Lake Michigan...
There is the potential that a somewhat separate corridor of
severe-weather potential may unfold today, potentially born out of
subtle mid-level wave and early morning convection across northeast
Missouri vicinity and/or development later today. The initially
elevated storms would be on the edge of the
east/northeastward-advecting elevated mixed layer. Steep mid-level
lapse rates and 35+ kt effective shear could support initially
isolated hail potential, but a more organized surface-based severe
risk could manifest if some of the more-aggressive early morning
short-term guidance trends materialize (HRRR/RAP/RRFS).

...Southern Plains including Oklahoma/Texas...
A moist and potentially unstable air mass will persist regionally to
the east of a dryline located around peak heating from east-central
Kansas south-southwestward into west-central Oklahoma and western
north Texas to the Texas Big Bend vicinity. Immediately east of the
dryline, warm-sector dewpoints are expected to generally be in the
middle 60s F, supporting MLCAPE values to 2500-3000 J/kg.

The extent/likelihood of sustained deep convection later today is a
key question. The primary southern-stream trough will be well
upstream over the southwest Desert, with neutral height tendencies
across the southern Plains, although early morning water vapor
imagery and derived wind data suggest that a subtle disturbance over
northern Mexico and the southern Rockies could approach the
dryline/warm sector later today.

Regardless, ample post-dryline mixing and near-dryline
confluence/weak convergence may be sufficient for deep convective
initiation after 21z/4pm CDT, at least an isolated basis. Forecast
mass fields would imply that this is most probable across
central/southwest Oklahoma into the north Texas Big Country, and
perhaps somewhat separately across the Texas Big Bend and Rio Grande
vicinity.

If/where storms develop and mature, deep-layer shear on the order of
40+ kt will support supercells, potentially capable of all hazards
including very large hail. An increased confidence in deep
convective initiation late this afternoon/early evening could
warrant focus Slight Risk delineations in subsequent Day 1 updates.

...Northern High Plains...
Generally isolated severe storms capable of hail/wind will be
possible late this afternoon into evening along/north of the surface
front where modest low-level moisture and vertical shear will be
maximized, in the presence of steep low/mid-level lapse rates.

..Guyer/Broyles.. 04/13/2026

$$

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ACUS01 KWNS 131638
SWODY1
SPC AC 131636

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1136 AM CDT Mon Apr 13 2026

Valid 131630Z - 141200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHERN MINNESOTA...FAR NORTHERN IOWA...AND PARTS OF WISCONSIN...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE
SOUTHERN PLAINS...

...SUMMARY...
Severe thunderstorms are likely across the Upper Mississippi Valley
and Great Lakes region with potential for large to very large hail,
damaging wind, and tornadoes, mainly late this afternoon into
tonight. A more isolated risk for severe storms is possible across
portions of the southern Plains late this afternoon and evening.

...Upper Mississippi Valley/Great Lakes including MN/WI/IA...
Multiple lead mid-level disturbances over the northern High Plains
will progress northeastward today toward the Upper Midwest, with
strengthening winds aloft across this region particularly late today
and tonight. A surface low will tend to deepen/develop
east-northeastward from northeast Nebraska into far southern
Minnesota and Wisconsin by tonight in vicinity of a
slow-moving/stalled frontal boundary. Low/middle 60s F surface
dewpoints will advect north-northeastward and become increasingly
prevalent along/south of the aforementioned stationary/warm front
this afternoon. MLCAPE values are forecast to reach 2000-2500 J/kg
by around 21z/4pm CDT.

Thunderstorm development will become increasingly probable through
mid/late afternoon (21-00z) as isentropic ascent strengthens ahead
of the approaching upper disturbance. This should especially be the
case near the primary boundary. However, semi-discrete warm sector supercellular development, across areas such as southern Wisconsin,
cannot be ruled out. Lingering inhibition coupled with 45-50 kt
effective bulk shear should promote initially discrete supercells.
Hodograph elongation appears favorable for a large hail threat,
possibly as large as 2-3 inches in diameter with the more robust
cells. Additionally, enhanced low-level SRH along the frontal zone
is expected to result in a corridor of relatively higher tornado
potential for storms that can remain rooted immediately along the
boundary.

While the overall environment appears very favorable for intense convection/supercells, east-northeasterly storm motions along or
just north of the warm front will likely promote clustering/upscale
growth through the evening, with an increasing damaging wind
potential and a continued tornado risk via line-embedded
circulations.

...Northern Illinois/northern Indiana and southern Lake Michigan...
See Mesoscale Discussion 395 for short-term details. There is the
potential that a somewhat separate corridor of severe-weather
potential today, potentially via a subtle mid-level wave and morning
convection across northeast Missouri/northwest Illinois vicinity
and/or additional development later today. The initially elevated
storms are on the edge of the east/northeastward-advecting elevated
mixed layer. Steep mid-level lapse rates and 35+ kt effective shear
could support initially isolated hail potential, but a more
organized surface-based severe risk could materialize later this
afternoon, although the specific details remain uncertain.

...Southern Plains including Oklahoma/Texas...
Confidence/potential for isolated to widely scattered locally
intense storms later this afternoon has incrementally increased,
although specifics regarding the extent of convective initiation are
still uncertain.

A moist and potentially unstable air mass will persist regionally to
the east of a dryline located around peak heating from east-central
Kansas south-southwestward into west-central Oklahoma and western
north Texas to the Texas Big Bend vicinity. Immediately east of the
dryline, warm-sector dewpoints are expected to generally be in the
middle 60s F, supporting MLCAPE values to 2500-3000 J/kg. A subtle
disturbance over northern Mexico and the southern Rockies could
approach the dryline/warm sector later today.

Regardless, ample post-dryline mixing and near-dryline
confluence/weak convergence should be sufficient for isolated deep
convective initiation after 21z/4pm CDT. Forecast mass fields and
some short-term guidance would imply that this is most probable
across central/southwest Oklahoma into the north Texas Big Country,
and perhaps somewhat separately across the Texas Big Bend and Rio
Grande vicinity.

If/where storms develop and mature, deep-layer shear on the order of
40+ kt will support supercells, potentially capable of all hazards
including very large hail.

...Northern High Plains...
Generally isolated severe storms including a few low-topped
supercells capable of hail/wind are possible late this afternoon
into evening along/north of the surface front. This is where modest
low-level moisture and vertical shear will be maximized, in the
presence of steep low/mid-level lapse rates.

..Guyer/Chalmers.. 04/13/2026

$$

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ACUS01 KWNS 131957
SWODY1
SPC AC 131956

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0256 PM CDT Mon Apr 13 2026

Valid 132000Z - 141200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PARTS OF
SOUTHERN MINNESOTA...NORTHERN IOWA...AND CENTRAL WISCONSIN...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF TEXAS...OKLAHOMA AND THE CENTRAL GREAT LAKES....

...SUMMARY...
Severe thunderstorms remain likely across the Upper Mississippi
Valley and Great Lakes region with potential for large to very large
hail, damaging wind, and tornadoes, mainly late this afternoon into
tonight. A more isolated risk for severe storms is possible across
portions of the southern Plains late this afternoon and evening.

...20z Update Upper Midwest...
Afternoon visible imagery showed diurnal heating ongoing south of
the stalled front from the eastern SD across southern MN into
central WI. Moderate destabilization should support scattered to
numerous thunderstorms this afternoon and evening. Initially
supercells are likely, given strongly veering wind profiles and
moderate deep-layer flow. All hazards are possible with these
storms. With time, upscale growth into one or more lines or clusters
appears likely as storms spread eastward into the Great Lakes.

Convective development appears likely along the triple point near
the surface low from northeast/eastern NE into southeastern SD.
Supercell wind profiles and moderate buoyancy would support a risk
for large hail and some damaging wind gusts. A tornado or two may
occur as any supercells that develop move eastward into deeper
low-level moisture across northwestern IA and southern MN.

...Southern and Central Plains...
Towering cumulus along a dryline over parts of KS/OK/TX may support
isolated storm development late this afternoon. A conditionally
favorable environment (3000+ j/kg of MLCAPE and 35-40 kt effective
shear) for supercells will support a risk for all hazards. See MCD
#399 for short term information. The primary change for this outlook
was to extend severe probabilities northeastward into eastern KS.
Guidance and observational trends have shown an increased likelihood
of a storm or two this afternoon.

..Lyons.. 04/13/2026

.PREV DISCUSSION... /ISSUED 1136 AM CDT Mon Apr 13 2026/

...Upper Mississippi Valley/Great Lakes including MN/WI/IA...
Multiple lead mid-level disturbances over the northern High Plains
will progress northeastward today toward the Upper Midwest, with
strengthening winds aloft across this region particularly late today
and tonight. A surface low will tend to deepen/develop
east-northeastward from northeast Nebraska into far southern
Minnesota and Wisconsin by tonight in vicinity of a
slow-moving/stalled frontal boundary. Low/middle 60s F surface
dewpoints will advect north-northeastward and become increasingly
prevalent along/south of the aforementioned stationary/warm front
this afternoon. MLCAPE values are forecast to reach 2000-2500 J/kg
by around 21z/4pm CDT.

Thunderstorm development will become increasingly probable through
mid/late afternoon (21-00z) as isentropic ascent strengthens ahead
of the approaching upper disturbance. This should especially be the
case near the primary boundary. However, semi-discrete warm sector supercellular development, across areas such as southern Wisconsin,
cannot be ruled out. Lingering inhibition coupled with 45-50 kt
effective bulk shear should promote initially discrete supercells.
Hodograph elongation appears favorable for a large hail threat,
possibly as large as 2-3 inches in diameter with the more robust
cells. Additionally, enhanced low-level SRH along the frontal zone
is expected to result in a corridor of relatively higher tornado
potential for storms that can remain rooted immediately along the
boundary.

While the overall environment appears very favorable for intense convection/supercells, east-northeasterly storm motions along or
just north of the warm front will likely promote clustering/upscale
growth through the evening, with an increasing damaging wind
potential and a continued tornado risk via line-embedded
circulations.

...Northern Illinois/northern Indiana and southern Lake Michigan...
See Mesoscale Discussion 395 for short-term details. There is the
potential that a somewhat separate corridor of severe-weather
potential today, potentially via a subtle mid-level wave and morning
convection across northeast Missouri/northwest Illinois vicinity
and/or additional development later today. The initially elevated
storms are on the edge of the east/northeastward-advecting elevated
mixed layer. Steep mid-level lapse rates and 35+ kt effective shear
could support initially isolated hail potential, but a more
organized surface-based severe risk could materialize later this
afternoon, although the specific details remain uncertain.

...Southern Plains including Oklahoma/Texas...
Confidence/potential for isolated to widely scattered locally
intense storms later this afternoon has incrementally increased,
although specifics regarding the extent of convective initiation are
still uncertain.

A moist and potentially unstable air mass will persist regionally to
the east of a dryline located around peak heating from east-central
Kansas south-southwestward into west-central Oklahoma and western
north Texas to the Texas Big Bend vicinity. Immediately east of the
dryline, warm-sector dewpoints are expected to generally be in the
middle 60s F, supporting MLCAPE values to 2500-3000 J/kg. A subtle
disturbance over northern Mexico and the southern Rockies could
approach the dryline/warm sector later today.

Regardless, ample post-dryline mixing and near-dryline
confluence/weak convergence should be sufficient for isolated deep
convective initiation after 21z/4pm CDT. Forecast mass fields and
some short-term guidance would imply that this is most probable
across central/southwest Oklahoma into the north Texas Big Country,
and perhaps somewhat separately across the Texas Big Bend and Rio
Grande vicinity.

If/where storms develop and mature, deep-layer shear on the order of
40+ kt will support supercells, potentially capable of all hazards
including very large hail.

...Northern High Plains...
Generally isolated severe storms including a few low-topped
supercells capable of hail/wind are possible late this afternoon
into evening along/north of the surface front. This is where modest
low-level moisture and vertical shear will be maximized, in the
presence of steep low/mid-level lapse rates.

$$

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ACUS01 KWNS 140056
SWODY1
SPC AC 140054

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0754 PM CDT Mon Apr 13 2026

Valid 140100Z - 141200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE UPPER MISSISSIPPI RIVER VALLEY...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS FAR EASTERN
KANSAS AND FAR WESTERN MISSOURI...

...SUMMARY...
Severe thunderstorms will continue across the Upper Mississippi
Valley and Great Lakes region with potential for large to very large
hail, damaging wind, and tornadoes, through the overnight hours. A
more focused risk for severe storms will continue through late
evening across the southern to central Plains.

...Synopsis...
Late-evening surface analysis reveals a slow-moving surface low over
eastern NE with a warm frontal zone draped eastward into southern MN
and central WI. Scattered strong to severe thunderstorms are ongoing
along the frontal zone as of 01 UTC and will likely continue through
much of the overnight hours across the upper MS Valley and the
Midwest. Further south, several attempts at convective initiation
have been noted along a dryline draped from eastern NE southward
into KS, OK, and TX. Although additional attempts at thunderstorm
development are possible over the next few hours, the primary severe
risk will be focused across the Kansas City metro area where a
cluster of supercells has emerged.

....Upper MS Valley/Midwest...
Scattered supercells are ongoing across southern MN and into central
WI along and north of the surface warm front. A tornado and
significant (2+ inch) hail threat will likely persist for the next
couple of hours, but the expectation is for increased storm
clustering and upscale growth through the overnight hours. The
developing MCS will likely spread east/southeast into southern WI
and possibly northern IL prior to 12 UTC Tuesday with an attendant
risk for severe winds.

...Eastern Kansas/western Missouri...
A cluster of supercells has emerged across eastern KS over the past
few hours and will likely continue to spread east into western MO
through late evening. Given very favorable thermodynamic and
kinematics noted in the 00z TOP sounding, this activity will likely
continue to pose a threat for very large hail and tornadoes. 15%
hail and 5% tornado probabilities have been introduced to account
for this localized threat.

...Southern Plains...
GOES imagery over the past few hours has shown several attempts at
convective initiation across OK and TX; however, most of these
attempts have failed due to very meager/localized ascent along the
dryline. While one strong storm is noted across northwest TX, the
potential for new storm development should wane through the evening
given residual inhibition noted in 00z soundings and as nocturnal
cooling begins to diminish the dryline circulation. Because of this,
opted to remove 15% risk probabilities, but maintain some risk
probabilities given the ongoing convection and otherwise very
favorable convective environment.

..Moore.. 04/14/2026

$$

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ACUS01 KWNS 140551
SWODY1
SPC AC 140550

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1250 AM CDT Tue Apr 14 2026

Valid 141200Z - 151200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF THE MIDWEST...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL
TO SOUTHERN PLAINS AND PARTS OF THE NORTHEAST...

...SUMMARY...
Severe thunderstorms are expected this afternoon through tonight
from the southern Plains to the Great Lakes. Large to very large
hail, a few tornadoes (some strong), and damaging wind gusts will be
possible, particularly across parts of eastern Iowa, northern
Illinois, and southern Wisconsin. Additional severe storms, mainly
producing strong wind gusts, will be possible across parts of the
Northeast this afternoon.

...Synopsis...
An upper wave is evident in recent water-vapor imagery across the
southern Great Basin. This trough will translate east into the
Plains through today, reaching the Great Lakes region by tonight.
This will support slight deepening of a diffuse surface low analyzed
over the central High Plains as it drifts east towards the lower MO
River Valley. Ahead of the low, an expansive warm sector
(characterized by widespread mid to upper 60s dewpoints) remains in
place from the southern Plains northeastward into the upper MS
Valley region. Strong to severe thunderstorms are expected along a
composite outflow boundary/warm front from eastern IA into southern
WI/northern IL as well as along a dryline draped from eastern KS
into OK and TX. Further east, a mid-level wave associated with
ongoing convection over the Great Lakes will support re-intensification/re-development of strong/severe storms across the
Northeast.

...Midwest...
An outflow boundary emanating from the ongoing MCS across the Great
Lakes will likely be draped across the Midwest early this morning.
This boundary is forecast to drift northward within a southerly flow
regime as an effective warm front ahead of the approaching surface
low and upper wave. Latest guidance generally depicts this boundary
stalling across eastern IA into southern WI by late afternoon when
daytime heating and ascent ahead of the upper wave will erode
inhibition and promote convective initiation along the boundary.

Dewpoints in the mid to upper 60s coupled with steep mid-level lapse
rates (already noted in upstream 00z RAOBs) will support MLCAPE
values near 2500 J/kg by late afternoon. Moderate buoyancy combined
with 45-55 knots of effective bulk shear will be highly favorable
for organized convection. Capping at the base of the EML should
initially limit thunderstorm coverage and favor discrete supercells
along the boundary. In addition to very large hail (possibly up to
2-3 inches in diameter), enhanced low-level SRH along the boundary
may support a corridor of locally higher tornado potential,
including the potential for significant tornadoes. With time,
easterly storm motions along the boundary will promote upscale
growth with an increasing wind threat heading into the late evening
hours.

The primary uncertainty will be the location of the boundary by late
afternoon. 30% hail and 10% tornado probabilities were adjusted to
reflect the most likely placement of the boundary based on a
consensus of guidance; however, exact placement of the boundary will
be conditional on the precise evolution of the morning MCS.
Similarly, how quickly upscale growth occurs after initiation may
modulate the duration of the significant hail/tornado threat.

...Kansas into Oklahoma and Texas...
Modest height falls across the central to southern Plains combined
with weak convergence along the dryline will likely support isolated
to perhaps scattered thunderstorms from eastern KS southward into TX
this afternoon. Consensus among latest HREF/REFS guidance is that
initiation is most probable across northwest TX into central OK -
possibly ahead of a subtle mid-level wave, though in reality the
unfocused nature of the broad-scale ascent suggests that initiation
will be possible anywhere along the dryline where low-level
convergence can be maximized. Regardless, ample buoyancy within the
warm sector (2500-3000 J/kg MLCAPE sampled in evening RAOBs) coupled
with 30-40 knots of effective bulk shear will support supercells
with an attendant threat for large hail (possibly exceeding 2 inches
in diameter). Some tornado threat will likely materialize around and
after 00 UTC as the nocturnal jet strengthens and enlarges low-level hodographs.

...Northeast...
A low-amplitude upper wave associated with an ongoing MCS across the
Great Lakes will migrate eastward towards the Northeast through the
day. Residual convection associated with the MCS may linger through
morning before re-intensifying by early afternoon as daytime heating
supports steepening low-level lapse rates and increasing MLCAPE
values (likely up to the 500-1000 J/kg range). While buoyancy will
likely remain weak, 35-40 knot bulk shear through the CAPE-bearing
layer and focused ascent ahead of a low-amplitude upper wave will
likely support organization of convective bands with an attendant
threat for strong to severe winds.

..Moore/Wendt.. 04/14/2026

$$

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ACUS01 KWNS 141239
SWODY1
SPC AC 141237

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0737 AM CDT Tue Apr 14 2026

Valid 141300Z - 151200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR IOWA INTO
THE SOUTHERN GREAT LAKES AND PORTIONS OF OKLAHOMA...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE
NORTHEAST...

...SUMMARY...
Severe thunderstorms are expected this afternoon through tonight
from the southern Plains into the Midwest. Large to giant hail,
several tornadoes (some strong), and severe gusts will be possible, particularly from Iowa into the southern Great Lakes.

...Midwest...
An MCV near the IL-IN border this morning and southward-moving
outflow are linked to thunderstorms over parts of the eastern Corn
Belt. This outflow boundary will likely stall with the western
portion of the boundary advancing northward within a strengthening
warm conveyor this afternoon. Guidance generally depicts this
boundary stalling across eastern IA into southern WI by late
afternoon when daytime heating and ascent ahead of the upper wave
will erode inhibition and promote convective initiation along the
boundary. A moist airmass upstream over the lower MO Valley will
advect northeast beneath steep 700-500 mb lapse rates (reference the
12 UTC Topeka, KS raob). MLCAPE at or above 2500 J/kg is forecast
by mid-late afternoon from IA into the IA-WI-IL border vicinity.
Initial storms later this afternoon will rapidly become supercells
with all severe hazards possible. Large to giant hail and an
intense tornado will be possible with the more mature/strongest
supercells where SRH is locally maximized near the boundary.
Upscale growth into a severe cluster is forecast to eventually
evolve during the evening aided by a strong southwesterly LLJ into
the southern Great Lakes. If a supercell develops ahead of the
eastward-moving cluster, a tornado threat could develop as the
boundary layer quickly recovers/destabilizes.

...Kansas into Oklahoma and Texas...
Modest height falls across the central to southern Plains combined
with weak convergence along the dryline will likely support
scattered thunderstorms from eastern KS southward into western north
TX this afternoon into the evening. Aligning with earlier thinking,
strong heating and perhaps weak ascent tied to a subtle mid-level
wave, will favor storm development by 20-22z as convective
inhibition erodes. A very unstable airmass characterized by
2500-3000 J/kg MLCAPE and elongated hodographs will strongly favor
supercells. The strength of low-level shear remains unclear during
the early evening, when the tornado risk could maximize.
Nonetheless, increased confidence in widely scattered to scattered
supercells yielding a risk for large to giant hail prompted an
increase in hail and hail-intensity highlights this outlook update.

...Northeast...
A low-amplitude disturbance associated with an ongoing MCS near Lake
Ontario this morning will move east into the Northeast during the
day. Cloud breaks and low-level warm/moist advection will
contribute to a destabilizing airmass by midday. Veering and
strengthening winds with height will support storm organization,
including the potential for supercells. Eventually a band of storms
is forecast to evolve by mid-late afternoon with wind damage being
the primary risk. Have introduced low hail/tornado probabilities to
account for hazards associated with supercells.

..Smith/Dean.. 04/14/2026

$$

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ACUS01 KWNS 141632
SWODY1
SPC AC 141630

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1130 AM CDT Tue Apr 14 2026

Valid 141630Z - 151200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE MIDWEST/SOUTHERN GREAT LAKES AND SOUTHERN/CENTRAL PLAINS...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE NORTHEAST...

...SUMMARY...
Severe thunderstorms are expected this afternoon through tonight
from the southern Plains into the Midwest. Large to giant hail,
several tornadoes (some strong), and swaths of severe/damaging gusts
are all likely, particularly from Iowa into the southern Great
Lakes.

...Synopsis...
An active severe weather day is anticipated for much of the
southern/central Plains into the Midwest/Great Lakes and parts of
the Northeast. The primary upper trough centered over the Four
Corners late this morning will eject east-northeastward towards the southern/central Plains by this evening, while a separate mid-level
shortwave trough over the northern Plains/Upper Midwest will also
move east-northeastward across the Upper Great Lakes into Ontario.
Another convectively enhanced low-amplitude shortwave trough will
also develop eastward across the Lower Great Lakes into the
Northeast.

Recent surface analysis indicates multiple surface lows, with one
over southern Ontario and another over southeast NE/northeast KS. A
seasonably rich/moist low-level airmass exists to the south of a
front extending between these two lows, with surface dewpoints
already in the low to mid 60s across much of the southern/central
Plains to the east of a dryline. Both the dryline in the
southern/central Plains and developing warm front in the
Midwest/southern Great Lakes will likely serve as foci for intense thunderstorms this afternoon and evening, including the potential
for several supercells.

...Midwest/Ohio Valley/Great Lakes...
A complex scenario for severe thunderstorms remains apparent across
the Midwest/OH Valley into the southern Great Lakes today, with
multiple outflow boundaries from earlier convection rendering
greater than usual uncertainty with the southward extent of possible thunderstorm development in IL/IN/OH. In general, continued
low-level warm advection from the central Plains into the Midwest/OH
Valley will support a moistening/destabilizing airmass through the
afternoon as a northern-stream shortwave trough moves eastward
across the Upper Midwest. A surface warm front will extend
northeastward from a weak surface low in IA across southern WI and
Lower MI. It still appears likely that multiple intense supercells
will develop by 20-21Z along/near this boundary in IA/southern
WI/northern IL in a very favorable airmass for significant severe
hail given strong deep-layer shear and the presence of steep
mid-level lapse rates. Low-level shear is expected to gradually
strengthen through the evening in tandem with a modestly increasing south-southwesterly low-level jet.

Any supercells than can remain on the warm/south side of the front
will be capable of producing tornadoes, a few of which could be
strong (EF-2/3). Some consideration was given to including greater
tornado probabilities and a Moderate Risk (level 4 of 5) focused
across southern WI/far northern IL. But, convection may have a
tendency to grow upscale fairly quickly this evening, so confidence
was not high enough for a categorical upgrade at this time.
Regardless, very large to giant hail (potentially up to 3-4 inches
in diameter) will be a threat with sustained supercells, and a swath
of severe/damaging winds appears likely with a convective cluster
spreading eastward across southern Lower MI this evening into
tonight.

A somewhat separate area of severe potential should also exist
farther south across central IL into IN/OH this afternoon and
evening. Greater low-level moisture and related instability are
expected to exist across these areas compared to locations farther
north. While large-scale forcing should remain fairly weak/nebulous
across this region, a remnant outflow boundary may provide a focus
for supercell development across central IL into IN by 20-21Z. Have
expanded the Slight Risk for large hail, damaging winds, and perhaps
a few tornadoes southward across these areas to account for this
still somewhat uncertain potential.

...Southern/Central Plains...
12Z observed soundings from DRT/MAF/FWD/OUN/TOP show the presence of
steep mid-level lapse rates atop rich low-level moisture (generally
14-15 g/kg mean mixing ratios) along/east of the surface dryline.
Southwesterly mid-level flow and modest ascent preceding the upper
trough over the Southwest/southern Rockies will gradually overspread
the warm sector by mid to late afternoon. Moderate to strong
instability (MLCAPE around 2000-3000 J/kg, locally stronger
possible) and 35-45 kt of deep-layer shear will support multiple
intense supercells. Explosive convective initiation across parts of
western OK into south-central/southeast KS is expected by 20-21Z as
lingering MLCIN erodes with filtered daytime heating and as
convective temperatures are breached.

The overall thermodynamic and kinematic environment appears quite
favorable for very large to potentially giant hail (up to 3-4 inches
in diameter) with any supercells that spread east-northeastward
through the afternoon/evening. A gradually strengthening low-level
jet across OK/KS by 00Z will also support a threat for a few
tornadoes, a couple of which could be strong as low-level hodographs
become enlarged. Gradual upscale growth/clustering should occur with
time through the evening, with some risk for severe/damaging winds.
The Enhanced Risk has been expanded a bit northeastward into south-central/southeast KS for a focused severe wind corridor.
Farther south along the length of the dryline in TX, isolated to
scattered supercells may develop this afternoon and evening, with a
risk for mainly large to very large hail and occasional severe
gusts.

...Northeast...
Ongoing convection across southern Ontario and the Lower Great Lakes
will continue to track eastward this afternoon into NY and parts of
New England in tandem with a low-amplitude shortwave trough. Gradual
clearing of low/mid-level clouds has already encouraged surface
temperatures to warm into the 70s along/south of west-east oriented
front. Thunderstorms are expected to gradually increase in coverage
and intensity as weak to locally moderate instability and strong
deep-layer shear support organized updrafts, including the potential
for some supercells initially. The greatest severe risk will
probably be scattered damaging winds given a tendency for convection
to consolidate into one or more clusters. But, an isolated severe
hail threat may exist with any sustained supercell, along with some
chance for a tornado or two near the front where low-level shear
will be locally enhanced.

..Gleason/Chalmers.. 04/14/2026

$$

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ACUS01 KWNS 141938
SWODY1
SPC AC 141936

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0236 PM CDT Tue Apr 14 2026

Valid 142000Z - 151200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE MIDWEST/SOUTHERN GREAT LAKES AND SOUTHERN/CENTRAL PLAINS...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE NORTHEAST...

...SUMMARY...
Severe thunderstorms are expected this afternoon through tonight
from the southern Plains into the Midwest. Large to giant hail,
several tornadoes (some strong), and swaths of severe/damaging gusts
are all likely, particularly from Iowa into the southern Great
Lakes.

...20Z Update...
A complex yet active severe weather day remains in the forecast for
portions of the Midwest-OH Valley into the Southern Plains this
afternoon into early tonight. While several lines were slightly
adjusted to account for the latest guidance consensus, the following substantial changes and/or decisions were made:

1.) 30 percent wind probabilities were expanded southwestward into
southwest and central OK to account for the possibility of more
rapid upscale growth into one or more wind-producing MCSs or linear
segments.

2.) Category 1/Marginal Risk probabilities for severe wind and hail
were expanded west-southwest into NE along a frontal boundary to
account for two possible scenarios. First, an isolated strong storm
may develop within the next few hours along the boundary as a
consequence of strong diurnal heating. Second, late tonight, there
is low potential for gravity-wave associated convection on the
immediate cool side of the frontal boundary, atop a stable boundary
layer.

3.) Confidence is still too low for supercells across the Midwest to
remain discrete for long periods of time, which would warrant a
Categorical Moderate risk upgrade. Nonetheless, should a dominant
supercell become sustained and discrete for at least a few hours,
especially along the warm front over northeast IA into southern WI,
a sustained and intense tornado will be possible.

The rest of the forecast (see below) remains on track.

..Squitieri.. 04/14/2026

.PREV DISCUSSION... /ISSUED 1130 AM CDT Tue Apr 14 2026/

...Synopsis...
An active severe weather day is anticipated for much of the
southern/central Plains into the Midwest/Great Lakes and parts of
the Northeast. The primary upper trough centered over the Four
Corners late this morning will eject east-northeastward towards the southern/central Plains by this evening, while a separate mid-level
shortwave trough over the northern Plains/Upper Midwest will also
move east-northeastward across the Upper Great Lakes into Ontario.
Another convectively enhanced low-amplitude shortwave trough will
also develop eastward across the Lower Great Lakes into the
Northeast.

Recent surface analysis indicates multiple surface lows, with one
over southern Ontario and another over southeast NE/northeast KS. A
seasonably rich/moist low-level airmass exists to the south of a
front extending between these two lows, with surface dewpoints
already in the low to mid 60s across much of the southern/central
Plains to the east of a dryline. Both the dryline in the
southern/central Plains and developing warm front in the
Midwest/southern Great Lakes will likely serve as foci for intense thunderstorms this afternoon and evening, including the potential
for several supercells.

...Midwest/Ohio Valley/Great Lakes...
A complex scenario for severe thunderstorms remains apparent across
the Midwest/OH Valley into the southern Great Lakes today, with
multiple outflow boundaries from earlier convection rendering
greater than usual uncertainty with the southward extent of possible thunderstorm development in IL/IN/OH. In general, continued
low-level warm advection from the central Plains into the Midwest/OH
Valley will support a moistening/destabilizing airmass through the
afternoon as a northern-stream shortwave trough moves eastward
across the Upper Midwest. A surface warm front will extend
northeastward from a weak surface low in IA across southern WI and
Lower MI. It still appears likely that multiple intense supercells
will develop by 20-21Z along/near this boundary in IA/southern
WI/northern IL in a very favorable airmass for significant severe
hail given strong deep-layer shear and the presence of steep
mid-level lapse rates. Low-level shear is expected to gradually
strengthen through the evening in tandem with a modestly increasing south-southwesterly low-level jet.

Any supercells than can remain on the warm/south side of the front
will be capable of producing tornadoes, a few of which could be
strong (EF-2/3). Some consideration was given to including greater
tornado probabilities and a Moderate Risk (level 4 of 5) focused
across southern WI/far northern IL. But, convection may have a
tendency to grow upscale fairly quickly this evening, so confidence
was not high enough for a categorical upgrade at this time.
Regardless, very large to giant hail (potentially up to 3-4 inches
in diameter) will be a threat with sustained supercells, and a swath
of severe/damaging winds appears likely with a convective cluster
spreading eastward across southern Lower MI this evening into
tonight.

A somewhat separate area of severe potential should also exist
farther south across central IL into IN/OH this afternoon and
evening. Greater low-level moisture and related instability are
expected to exist across these areas compared to locations farther
north. While large-scale forcing should remain fairly weak/nebulous
across this region, a remnant outflow boundary may provide a focus
for supercell development across central IL into IN by 20-21Z. Have
expanded the Slight Risk for large hail, damaging winds, and perhaps
a few tornadoes southward across these areas to account for this
still somewhat uncertain potential.

...Southern/Central Plains...
12Z observed soundings from DRT/MAF/FWD/OUN/TOP show the presence of
steep mid-level lapse rates atop rich low-level moisture (generally
14-15 g/kg mean mixing ratios) along/east of the surface dryline.
Southwesterly mid-level flow and modest ascent preceding the upper
trough over the Southwest/southern Rockies will gradually overspread
the warm sector by mid to late afternoon. Moderate to strong
instability (MLCAPE around 2000-3000 J/kg, locally stronger
possible) and 35-45 kt of deep-layer shear will support multiple
intense supercells. Explosive convective initiation across parts of
western OK into south-central/southeast KS is expected by 20-21Z as
lingering MLCIN erodes with filtered daytime heating and as
convective temperatures are breached.

The overall thermodynamic and kinematic environment appears quite
favorable for very large to potentially giant hail (up to 3-4 inches
in diameter) with any supercells that spread east-northeastward
through the afternoon/evening. A gradually strengthening low-level
jet across OK/KS by 00Z will also support a threat for a few
tornadoes, a couple of which could be strong as low-level hodographs
become enlarged. Gradual upscale growth/clustering should occur with
time through the evening, with some risk for severe/damaging winds.
The Enhanced Risk has been expanded a bit northeastward into south-central/southeast KS for a focused severe wind corridor.
Farther south along the length of the dryline in TX, isolated to
scattered supercells may develop this afternoon and evening, with a
risk for mainly large to very large hail and occasional severe
gusts.

...Northeast...
Ongoing convection across southern Ontario and the Lower Great Lakes
will continue to track eastward this afternoon into NY and parts of
New England in tandem with a low-amplitude shortwave trough. Gradual
clearing of low/mid-level clouds has already encouraged surface
temperatures to warm into the 70s along/south of west-east oriented
front. Thunderstorms are expected to gradually increase in coverage
and intensity as weak to locally moderate instability and strong
deep-layer shear support organized updrafts, including the potential
for some supercells initially. The greatest severe risk will
probably be scattered damaging winds given a tendency for convection
to consolidate into one or more clusters. But, an isolated severe
hail threat may exist with any sustained supercell, along with some
chance for a tornado or two near the front where low-level shear
will be locally enhanced.

$$

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ACUS01 KWNS 150056
SWODY1
SPC AC 150054

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0754 PM CDT Tue Apr 14 2026

Valid 150100Z - 151200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROS PORTIONS
OF THE GREAT LAKES REGION...

...SUMMARY...
Severe thunderstorms are expected through tonight from the southern
Plains into the Midwest. Large hail, several tornadoes (some
strong), and swaths of severe/damaging gusts are all likely,
particularly from eastern Iowa into the southern Great Lakes.

...Synopsis...
Scattered discrete/semi-discrete supercells are ongoing across
eastern Iowa, far northern Illinois, and southern Wisconsin along a
diffuse warm frontal zone stretching eastward from weak surface low
analyzed over eastern NE/western IA. The primary severe risk through
the overnight hours will be associated with this activity as it
spreads southeast through early morning. Further south across the central/southern Plains, poorly organized convection casts
uncertainty in the nocturnal severe threat; however, a favorable
environment will remain in place through Wednesday morning and could
support severe convection.

...Midwest/Great Lakes...
01 UTC regional radar mosaics show semi-discrete supercells ongoing
across far eastern IA, northern IL, and southern WI with the early
stages of upscale growth evident as storms interactions increase.
This trend will continue through the overnight hours as this
activity propagates east/southeast into lower MI and northern IN.
The recent 00z DVN RAOB sampled a convective environment highly
favorable for organized convection, which will maintain the
potential for significant hail and tornadoes in the near term (most
likely through 03 UTC) before a full transition to a linear mode
takes place. Once this transition occurs, severe winds (including
the potential for significant gusts in excess of 75 mph) and
embedded circulations appear probable for areas downstream.

...Southern Iowa into Kansas...
Thunderstorm development along a southward sagging cold front is
anticipated in the coming hours across northeast KS into southern
IA. Regional soundings sampled adequate buoyancy and strong
deep-layer wind shear (around 50 knots) that will likely support
organized convection along the front for a few hours. Storm motions
along the boundary may foster clustering/upscale growth, but a
severe wind, hail, and perhaps tornado threat is expected to
materialize through the night.

...Oklahoma into Texas...
Convective evolution thus far across western OK into northwest TX
has been relatively lackluster given the otherwise buoyant and
strongly sheared environment sampled by the 00z OUN sounding. This
is likely due to expansive convective outflows resulting in
undercutting and clustered storm modes as well as the presence of a
subsidence inversion (also noted in the 00z sounding). It remains
unclear whether or not this activity will be able to re-intensify
through the late evening hours given. However, strengthening flow
fields through 06 UTC may support some degree of improved
organization and a more robust severe threat. This potential is
hinted by recent HRRR solutions, but overall confidence is limited.
Based on these trends, opted to remove the 30% hail/wind
probabilities given low confidence in severe coverage. Further south
into western TX, attempts at sustained convection have been noted
over the past hour along the dryline, but downstream inhibition may
limit overall storm coverage.

..Moore.. 04/15/2026

$$

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ACUS01 KWNS 150554
SWODY1
SPC AC 150553

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1253 AM CDT Wed Apr 15 2026

Valid 151200Z - 161200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE
SOUTHERN PLAINS...MIDWEST...AND INTO THE GREAT LAKES...

...SUMMARY...
Severe thunderstorms posing a risk for large hail, strong wind
gusts, and a couple of tornadoes will be possible across portions of
the southern Plains toward the Great Lakes this afternoon and
evening.

...Synopsis...
A migratory upper-level wave is evident in water-vapor imagery over
northern Mexico. This feature will lift northeastward into the
Plains through the day, resulting in the eastward progression of a
modest surface cyclone from the central High Plains into eastern NE
by late afternoon. A broad, uncapped, and moderately sheared warm
sector will be in place from the southern Plains into the mid-MS
Valley and eastward into the Great Lakes/OH Valley. Strong to severe thunderstorm development appears probable across much of this warm
sector, whether induced by ascent ahead of the primary upper wave or
by localized mesoscale boundaries.

...Iowa and northern Missouri...
Thunderstorm development appears likely by late afternoon from
central IA into northern MO in the vicinity of the surface low.
Stronger mid-level height falls compared to previous days lends
higher confidence in thunderstorm development, and 50-60 knot 500 mb
flow overspreading much of the warm sector will support organized
convection, including the potential for splitting supercells capable
of very large hail and tornadoes across IA and northern MO. A
focused zone of higher tornado potential may emerge roughly along
the I-80 corridor where backed low-level winds along the effective
warm front will locally augment SRH and could support a strong
tornado. HREF/REFS guidance both show the strongest UH signals
across this zone, warranting higher (5%) tornado probabilities.

...Ozarks into Oklahoma and north Texas...
Further south, initially discrete cells are anticipated along the
dryline from southeast KS into OK and north TX by mid-afternoon.
Despite somewhat higher confidence in storm development compared to
previous days, mean flow vectors along the boundary may promote
clustering and upscale growth within a few hours after initiation.
This scenario appears to be reflected in recent HREF/REFS guidance
in the form of numerous, but weak, UH streaks, as well as in
deterministic CAM solutions that depict one or more convective bands
emerging by early evening. Additionally, guidance hints at the
potential for morning convection across parts of OK and the Ozark
Plateau. It remains unclear what influence - if any- this activity
will have on the southern Plains warm sector or if any outflow
boundaries can emerge and focus a higher severe threat along
mesoscale corridors. Given these uncertainties, all severe
probabilities were expanded to account for the fairly wide envelope
of potential outcomes, most of which will likely feature the
potential for severe hail, wind, and tornadoes.

...Great Lakes into New England...
The combination of low to mid-60s dewpoints and the eastward
advection of an EML will support MLCAPE values upwards of 1000-1500
J/kg across much of the Great Lakes region with gradually
diminishing buoyancy with eastward extent towards the New England
coast. Aloft, 40-50 knot westerly mid-level winds will remain in
place within the crest of a modest ridge, establishing a zonal
corridor of a buoyant and moderately sheared environment. It appears
likely that multiple outflow boundaries and/or mid-level
perturbations associated with upstream MCSs across MI, AR, and IA
will likely reside within the warm sector by peak heating.
Thunderstorm development along or in the vicinity of these features
will support multiple corridors of strong to severe convection. This
scenario is depicted by most recent CAMs, which show multiple
convection bands traversing the warm sector through early evening.
However, exactly where these bands will become established (and
where corridors of higher severe potential will emerge) remains
uncertain given variance in recent guidance.

..Moore/Wendt.. 04/15/2026

$$

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ACUS01 KWNS 151247
SWODY1
SPC AC 151246

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0746 AM CDT Wed Apr 15 2026

Valid 151300Z - 161200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE SOUTHERN
PLAINS INTO THE MIDWEST AND SOUTHERN GREAT LAKES...

...SUMMARY...
Severe thunderstorms posing a risk for large hail to very large
hail, severe gusts, and a couple of tornadoes will be possible
across portions of the southern Plains toward the Great Lakes this
afternoon and evening.

...Synopsis...
Water-vapor imagery this morning shows an upper trough from the
eastern Dakotas south-southwestward into the southern Rockies. A
few disturbances will migrate eastward coincident with the trough
with the most notable being over the central High Plains this
morning. The aforementioned disturbance will move east reaching the
mid-upper MS Valley with the trailing southern extent of the wave
moving into the MO Ozarks and OK by daybreak Thursday. A weak
diffuse low will move from northern KS to the southwest Great Lakes
by late tonight. Farther east, an MCV near MO-IL will translate
east and become perhaps a focus for storm activity later this
afternoon across OH-PA. A rather complex forecast is apparent due
in large part to considerable convection and related outflow
permeating the warm sector overnight across much of the Slight-Risk
area.

...Iowa into the mid MS Valley...
In the wake of showers/storms this morning from IA southward into
MO, a moist and weakly capped airmass will destabilize through early
afternoon. The eastward approach of the mid-level disturbance will
likely contribute towards scattered thunderstorms developing 19-21z
from near the weak low eastward along the composite outflow/frontal
zone into IL-WI and southward into MO within a weakly capped warm
sector. Forecast soundings show straight-line hodographs over IA
with sizable CAPE in the hail growth zone. The potential for
splitting supercells appears evident with the stronger storms
capable of very large hail and perhaps some tornado risk across IA
and northern MO.

...Ozarks into Oklahoma and north Texas...
Morning raobs showed steep 700-500 mb lapse rates (7.5-8 deg C/km)
atop a seasonably very moist return-flow airmass. Models generally
show storm development near the dryline by mid afternoon with
initial development becoming supercellular. Large to very large
hail will be possible with the stronger updrafts. Residual outflow
from overnight convection moving into the Ozarks may play a role in
enhancing low-level shear later today. Forecast soundings show
somewhat limited low-level hodographs with a tendency for a
veer-back-veer signature. Additional storms will favor some
clustering and upscale growth with time due in part to the forecast
hodographs. Nonetheless, all hazards will be possible at least
through the early convective life cycle before the possibility for
wind damage and linear structures perhaps evolve during the evening.

...Southern Great Lakes into the Northeast...
The remnants of an overnight squall line are moving east across
NY-PA this morning with a trailing outflow boundary extending
westward into OH and northeast IN. Moist low levels and the
eastward advection of steeper mid-level lapse rates will act to
destabilize the southern Great Lakes into western PA through midday
and into the afternoon. Forcing for ascent and enhancement of flow
associated with the MCV will potentially focus thunderstorms and aid
in their organization potential beginning this afternoon.
Considerable uncertainty remains regarding this scenario and whether
a mesoscale corridor of higher tornado probabilities is needed
(i.e., northeast OH). Will defer to later outlooks to where perhaps
mesoscale corridors of greater wind/hail threat and an isolated risk
for a couple of tornadoes could develop.

..Smith/Dean.. 04/15/2026

$$

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ACUS01 KWNS 151632
SWODY1
SPC AC 151630

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1130 AM CDT Wed Apr 15 2026

Valid 151630Z - 161200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE SOUTHERN/CENTRAL PLAINS INTO THE MIDWEST/OHIO VALLEY AND
SOUTHERN GREAT LAKES...

...SUMMARY...
Severe thunderstorms posing a risk for large to very large hail,
damaging winds, and perhaps a few tornadoes will be possible across
parts of the southern/central Plains into the Midwest/Ohio Valley
and southern Great Lakes this afternoon and evening.

...Synopsis...
Severe potential across the broad warm sector will be complicated by
ongoing thunderstorms/MCVs and associated cloud cover. A neutral to
positively tilted upper trough will eject northeastward across the southern/central Plains today, with a broad zone of enhanced
mid-level southwesterly winds extending over much of TX/OK into the
Midwest/OH Valley and Great Lakes. At the surface, a weak low over
southeast NE late this morning is forecast to develop slowly
northeastward across IA through the afternoon and evening, with a quasi-stationary front extending northeastward from this low towards
southern WI/Lower MI. A dryline extends southward across KS/OK into
west TX. Multiple MCVs related to ongoing/earlier convection are
also noted in recent visible satellite/radar imagery, and these
features may aid additional convective development this afternoon.

...Iowa into Missouri...
Forcing for ascent associated with the ejecting upper trough will
overspread the front draped across IA this afternoon. Ongoing
supercell in western IA and cloudiness near the front late this
morning cast some uncertainty on the degree of destabilization that
will occur this afternoon, and the overall intensity of convection.
Still, expectations are for additional robust thunderstorms to
eventually develop by 19-21Z along/near the front in IA, with steep
mid-level lapse rates noted on the observed 12Z TOP sounding
supporting moderate to locally strong MLCAPE even if
clouds/precipitation hinder daytime heating to some extent. Various
NAM/RAP forecast soundings show elongated/nearly straight hodographs
at mid/upper levels and 50+ kt of deep-layer shear, which will be
favorable for upper-level/anvil venting and hail production with any
supercells that form. Large to very large hail will be a concern
with initially discrete convection. But, some tendency for
clustering and movement north of the surface front casts
considerable uncertainty on the wind/tornado potential. Even so,
some chance for a few tornadoes and scattered damaging winds may
exist along/south of the front across IA into MO with any convection
that can develop east of the dryline.

...Southern Plains into the Ozarks and Mid Mississippi Valley...
A seasonably moist low-level airmass remains in place across the
southern Plains into the Ozarks and mid MS Valley, with observed 12Z
soundings from FWD/OUN/SGF indicating mean mixing ratios ranging
12-13.6 g/kg. However, even with steep mid-level lapse rates noted
across TX/OK, profiles are fairly saturated at mid/upper levels, and
plentiful cloud cover is present in recent visible satellite imagery
across these regions. It still appears likely that surface-based
thunderstorms will develop this afternoon (around 19-21Z) along/east
of the dryline as MLCIN gradually erodes ahead of the ejecting upper
trough. But, overall evolution remains somewhat unclear, with
potential for messy storm modes/interactions fairly early in the
convective life cycle given a large degree of boundary-parallel flow
in low/mid levels. Initial supercells should pose a threat for
mainly large to very large hail (isolated 2+ inches in diameter),
before clustering and an increase in damaging wind potential occurs.
The tornado threat is less clear, as stronger low-level flow will
tend to remain focused farther north into the Midwest. Still,
sufficient low-level shear should exist this afternoon and evening
to support a threat for a few tornadoes with both supercells and
embedded within clusters.

...Midwest/Ohio Valley into Western Pennsylvania...
An MCV evident over eastern IL/western IN will continue to track
eastward into northern IN and eventually OH this afternoon and
evening. Ongoing thunderstorms associated with this MCV have
remained sub-severe through much of the morning. But, gradual
destabilization of the already moist low-level airmass downstream
should support some uptick in convective coverage and intensity
across the OH Valley by mid to late afternoon. Localized enhancement
to the west-southwesterly low-level winds should focus across parts
of northern OH and vicinity, where somewhat greater low-level shear
and tornado potential may exist. Strong deep-layer shear will easily
support organized convection, including the potential for supercells
with a threat for large hail, damaging winds, and perhaps a couple
of tornadoes. Additional thunderstorms may eventually develop
eastward from the mid MS Valley into IL/IN in association with
another MCV. Large hail, damaging winds, and a tornado or two may
also occur with this activity, if it develops.

..Gleason/Squitieri.. 04/15/2026

$$

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ACUS01 KWNS 151957
SWODY1
SPC AC 151955

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0255 PM CDT Wed Apr 15 2026

Valid 152000Z - 161200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PARTS OF THE
SOUTHERN/CENTRAL PLAINS INTO THE MIDWEST/OHIO VALLEY AND SOUTHERN
GREAT LAKES...

...SUMMARY...
Severe thunderstorms posing a risk for large to very large hail,
damaging winds, and perhaps a few tornadoes will be possible across
parts of the southern/central Plains into the Midwest/Ohio Valley
and southern Great Lakes this afternoon and evening.

...20Z Update...

...Mid MS Valley through the Ozarks into the Southern Plains...
Recent surface analysis places a low in the NE/IA/MO border
intersection vicinity, with a dry line extending southwestward from
this low through eastern KS, western OK, and northwest TX. As
mentioned in MCD #448, the elevated supercell ongoing across central
IA could begin to interact with an environment more supportive of
surface-based storms. If a transition to surface-based is realized,
an increased potential for damaging gusts and a tornado will exist.
New development is also beginning across central IA, along the
outflow extending southwestward for this supercell. Hail remains the
primary risk across the region, both with the ongoing supercell and
any new development along its outflow.

Increasing thunderstorm coverage is still expected tonight along the
dryline as it shifts eastward, beginning across northwest TX and
central OK now before expanding northward into MO, and potentially southwestward into more of southwest TX later. Large hail remains
the primary threat with this initially more cellular activity. Some
very large hail (i.e. 2"+ in diameter) is possible. Over time,
storm interactions and/or upscale growth is anticipated, with a
trend towards a threat for more damaging gusts. Tornado threat
remains low, largely due weakness in the low to mid-level flow and
convective mode issues. However, some modest strengthening of the
low-level flow should exist this afternoon and evening from eastern
OK into the mid MS Valley, supporting a threat for a few tornadoes
with both supercells and embedded within clusters.

...OH Valley...
Severe Thunderstorm Watch #120 is currently ongoing from far
southeast Lower MI across northern OH into far northwest PA. Here, a
mix of clusters and supercells pose a threat for scattered damaging
winds and large hail as they spread quickly east-northeastward this
afternoon and evening. A tornado or two is also possible.

..Mosier.. 04/15/2026

.PREV DISCUSSION... /ISSUED 1130 AM CDT Wed Apr 15 2026/

...Synopsis...
Severe potential across the broad warm sector will be complicated by
ongoing thunderstorms/MCVs and associated cloud cover. A neutral to
positively tilted upper trough will eject northeastward across the southern/central Plains today, with a broad zone of enhanced
mid-level southwesterly winds extending over much of TX/OK into the
Midwest/OH Valley and Great Lakes. At the surface, a weak low over
southeast NE late this morning is forecast to develop slowly
northeastward across IA through the afternoon and evening, with a quasi-stationary front extending northeastward from this low towards
southern WI/Lower MI. A dryline extends southward across KS/OK into
west TX. Multiple MCVs related to ongoing/earlier convection are
also noted in recent visible satellite/radar imagery, and these
features may aid additional convective development this afternoon.

...Iowa into Missouri...
Forcing for ascent associated with the ejecting upper trough will
overspread the front draped across IA this afternoon. Ongoing
supercell in western IA and cloudiness near the front late this
morning cast some uncertainty on the degree of destabilization that
will occur this afternoon, and the overall intensity of convection.
Still, expectations are for additional robust thunderstorms to
eventually develop by 19-21Z along/near the front in IA, with steep
mid-level lapse rates noted on the observed 12Z TOP sounding
supporting moderate to locally strong MLCAPE even if
clouds/precipitation hinder daytime heating to some extent. Various
NAM/RAP forecast soundings show elongated/nearly straight hodographs
at mid/upper levels and 50+ kt of deep-layer shear, which will be
favorable for upper-level/anvil venting and hail production with any
supercells that form. Large to very large hail will be a concern
with initially discrete convection. But, some tendency for
clustering and movement north of the surface front casts
considerable uncertainty on the wind/tornado potential. Even so,
some chance for a few tornadoes and scattered damaging winds may
exist along/south of the front across IA into MO with any convection
that can develop east of the dryline.

...Southern Plains into the Ozarks and Mid Mississippi Valley...
A seasonably moist low-level airmass remains in place across the
southern Plains into the Ozarks and mid MS Valley, with observed 12Z
soundings from FWD/OUN/SGF indicating mean mixing ratios ranging
12-13.6 g/kg. However, even with steep mid-level lapse rates noted
across TX/OK, profiles are fairly saturated at mid/upper levels, and
plentiful cloud cover is present in recent visible satellite imagery
across these regions. It still appears likely that surface-based
thunderstorms will develop this afternoon (around 19-21Z) along/east
of the dryline as MLCIN gradually erodes ahead of the ejecting upper
trough. But, overall evolution remains somewhat unclear, with
potential for messy storm modes/interactions fairly early in the
convective life cycle given a large degree of boundary-parallel flow
in low/mid levels. Initial supercells should pose a threat for
mainly large to very large hail (isolated 2+ inches in diameter),
before clustering and an increase in damaging wind potential occurs.
The tornado threat is less clear, as stronger low-level flow will
tend to remain focused farther north into the Midwest. Still,
sufficient low-level shear should exist this afternoon and evening
to support a threat for a few tornadoes with both supercells and
embedded within clusters.

...Midwest/Ohio Valley into Western Pennsylvania...
An MCV evident over eastern IL/western IN will continue to track
eastward into northern IN and eventually OH this afternoon and
evening. Ongoing thunderstorms associated with this MCV have
remained sub-severe through much of the morning. But, gradual
destabilization of the already moist low-level airmass downstream
should support some uptick in convective coverage and intensity
across the OH Valley by mid to late afternoon. Localized enhancement
to the west-southwesterly low-level winds should focus across parts
of northern OH and vicinity, where somewhat greater low-level shear
and tornado potential may exist. Strong deep-layer shear will easily
support organized convection, including the potential for supercells
with a threat for large hail, damaging winds, and perhaps a couple
of tornadoes. Additional thunderstorms may eventually develop
eastward from the mid MS Valley into IL/IN in association with
another MCV. Large hail, damaging winds, and a tornado or two may
also occur with this activity, if it develops.

$$

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ACUS01 KWNS 160058
SWODY1
SPC AC 160057

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0757 PM CDT Wed Apr 15 2026

Valid 160100Z - 161200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS EVENING IN A
CORRIDOR FROM THE SOUTHEASTERN GREAT PLAINS THROUGH THE MIDWEST...

...SUMMARY...
Potential for damaging wind gusts could still increase a bit with
developing clusters of storms through mid to late evening across
parts of the Midwest into the southeastern Great Plains, while also
continuing with another cluster of storms spreading across northern
portions of the Allegheny Plateau.

...01Z Update...
Mid-level ridging centered near the south Atlantic Seaboard remains
prominent, but is undergoing some suppression as at least a couple
of short wave troughs migrate around its western through northern
periphery. The most substantive of these waves is forecast to
continue migrating northeast of the lower Missouri Valley through Wisconsin/Illinois by late tonight, accompanied by a modest
downstream surface frontal wave. A vigorous jet streak associated
with one or two lower amplitude downstream perturbations is forecast
to propagate from the lee of the lower Great Lakes through southern
New England. It appears that mid/upper troughing with embedded
low-amplitude perturbations will linger across parts of the southern
Great Plains.

Peak afternoon destabilization along the dryline, from near its
frontal intersection (roughly near/north of the Greater Kansas City
area) southwestward into the Texas South Plains, is already waning.
However, it appears that at least a narrow corridor of moderate
residual boundary-layer instability in the warm sector to its east
could may maintain vigorous convection and support continuing
upscale convective growth into mid/late evening across parts of
southeastern Oklahoma, western/northern Arkansas, central/eastern
Missouri and central/northern Illinois. As this occurs, largely
coincident with a northeastward propagating 30-40 kt southwesterly
850 mb jet, this may be accompanied by developing areas of
increasing potential for damaging wind gusts and perhaps a few brief
tornadoes, before convection weakens overnight.

..Kerr.. 04/16/2026

$$

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ACUS01 KWNS 160601
SWODY1
SPC AC 160559

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1259 AM CDT Thu Apr 16 2026

Valid 161200Z - 171200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON
ACROSS PARTS OF WESTERN AND CENTRAL NEW YORK INTO SOUTHERN
VERMONT...

...SUMMARY...
A few severe thunderstorms are possible this afternoon in a corridor
across western through central New York (state) and adjacent
southern Vermont.

...Discussion...
A significant mid-level trough and embedded low now digging across
the Pacific Northwest is forecast to split as it continues inland
through this period. One perturbation, perhaps including a
continuing cyclonic circulation, is forecast to turn eastward across
the northern Rockies through the central Canadian/U.S. border area.
Another perturbation is forecast to dig southeastward across the
Great Basin into early Friday. It appears that the larger-scale
evolving troughing will be preceded by a significant cold frontal
surge to the lee of the northern U.S. Rockies, through much of the
northern and central Great Plains by 12Z Friday.

Downstream, initially prominent mid-level ridging centered near the
southern Atlantic Seaboard is forecast to become increasingly
suppressed, as one short wave trough, approaching southwestern
portions of the Great Lakes region early today, turns eastward then southeastward across the lower Great Lakes vicinity into northern
Mid Atlantic. It appears that this will be trailed by another
perturbation, which is forecast to progress east of the Ozark
Plateau through the lower Ohio and Tennessee Valleys, before digging
across the southern Appalachians, downstream of short wave ridging
building across and east of the mid/upper Mississippi Valley.

...Mid South into lower Great Lakes and Northeast...
The primary and trailing short wave troughs advancing to the east of
the Mississippi Valley are forecast to be preceded by the remnants
of overnight convection across parts of the lower Great Lakes, Ohio
Valley, and Mid South at the outset of the period. The impacts of
associated cloud cover and outflow on destabilization within the
warm sector of a broad, but weak, surface low migrating northeast of
the lower Great Lakes during the day remain unclear. However,
various model output, including convection allowing guidance,
suggest that destabilization and strengthening shear along a warm
frontal zone (as it strengthens with differential heating) may
become a focus for organized strong thunderstorm development across
New York state by afternoon. It appears that this may include an
evolving cluster, perhaps preceded by more discrete thunderstorm
activity, in an environment conducive to evolving supercell
structures, with potential to produce severe hail, wind and a risk
for a couple of tornadoes.

Additional thunderstorm activity may eventually develop and
strengthen, accompanied by at least a risk for strong to severe wind
gusts by late afternoon, in a corridor of stronger daytime heating
ahead of a developing cold front spreading into the upper Ohio
Valley/Allegheny and Cumberland Plateau by late afternoon.

There is not a well-defined signal in the latest model output, but a
corridor of differential surface heating along weakening trailing
convective outflow across the Mid South vicinity could become a
focus for supercell development. It currently appears that this
potential could peak across north central into northeastern Arkansas
by late this afternoon, aided by moderate boundary-layer
destabilization and stronger mid-level forcing for ascent associated
with a cyclonic vorticity center migrating across the region.

...Southern Great Plains...
Moderate to strong potential instability is forecast to develop
beneath steep lapse rates, along and east of a dryline which likely
will be retreating westward across the high plains by early this
evening. While this will be conditionally support of severe
thunderstorm development, forcing to support initiation of sustained thunderstorms remains unclear, associated from, perhaps, the higher
terrain near/east of the Texas Big Bend. Beneath moderate to strong southwesterly mid/upper flow, this could include an isolated
supercell or two which could propagate across the Rio Grande River,
before weakening in the presence of increasing inhibition this
evening.

..Kerr/Lyons.. 04/16/2026

$$

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ACUS01 KWNS 161236
SWODY1
SPC AC 161234

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0734 AM CDT Thu Apr 16 2026

Valid 161300Z - 171200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR NEW YORK INTO
SOUTHERN VERMONT AND OVER THE NORTHERN HALF OF ARKANSAS...

...SUMMARY...
Scattered severe thunderstorms are possible this afternoon over New
York into southern Vermont with damaging gusts and perhaps a tornado
or two the primary threats. Large to very large hail is possible
with stronger storms over the northern half of Arkansas.

...Northeast southward into the central Appalachians and Cumberland
Plateau...
Water-vapor imagery this morning shows an upper trough over the
mid/upper MS Valley moving east towards the Northeast. A belt of
strong west-southwesterly 500-mb flow (50-65 kt) will overspread
much of the Northeast today in conjunction with the
eastward-migrating shortwave trough. Visible-satellite imagery
shows scattered to broken cloud cover to the south of a west-east
oriented frontal zone extending east from a surface low analyzed
over Lake Huron. Heating of an adequately moist boundary layer
(surface dewpoints in the 56-62 deg F range) will result in weak to
locally moderate buoyancy by midday into the mid afternoon (500-1250
J/kg MLCAPE). Large-scale ascent associated with the approaching
disturbance and convergence in the vicinity of the frontal zone will
lead to scattered storm development this afternoon. Ample mid to
high-level flow will favor storm organization, including the
possibility for a few supercells and an organized band of storms. A
risk for large hail and a tornado could accompany the more intense
cells, whereas the wind risk will tend to focus with linear
structures that evolve. An isolated threat for wind damage and
perhaps hail will extend southward into PA/WV and the Cumberland
Plateau, where a few stronger storms may yield those hazards.

...Mid South...
Satellite imagery shows the trailing portion of the upper shortwave
trough over the western Great Lakes is moving east across OK this
morning. This upper feature and associated mid-level cold pocket
(-16 to -18 deg C at 500 mb) will move across the MO Ozarks and AR
this afternoon. A reservoir of lower 60s deg F surface dewpoints
and strong heating in wake of early day showers and isolated
thunderstorms will favor robust CAPE profiles and elongated mid to
upper portions of the hodograph. Latest guidance shows several
cells developing within a weakly capped airmass by mid afternoon.
The stronger storms will likely become supercells yielding a risk
for large to very large hail (1 to 3 inches in diameter). Modest
low-level flow will tend to limit low-level mesocyclone intensity
and the lessen the overall tornado risk. A couple of smaller
clusters may evolve during the early evening with an isolated wind
threat potentially ensuing before this activity weakens by mid
evening.

...Edwards Plateau into the TX Big Country and western north TX...
Moderate to strong potential instability is forecast to develop
beneath steep lapse rates, along and east of a dryline. Although
neutral to weak shortwave ridging is expected today, some of the
latest model guidance shows isolated to widely scattered storm
development by late afternoon on the northwestern rim of richer
low-level moisture arcing from the Edwards Plateau into western
north TX. Strong heating will likely erode appreciable remaining
convective inhibition by 20-22 UTC. Strong west-southwesterly
100-kt 200-mb flow will elongate hodographs amidst a moderately
buoyant airmass. Widely spaced/isolated supercells will mainly
yield a large hail threat late this afternoon into the early
evening.

..Smith/Dean.. 04/16/2026

$$

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ACUS01 KWNS 161626
SWODY1
SPC AC 161624

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1124 AM CDT Thu Apr 16 2026

Valid 161630Z - 171200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR NEW YORK INTO
SOUTHERN VERMONT AS WELL AS FOR NORTHERN ARKANSAS...SOUTHERN
MISSOURI AND FAR WESTERN TENNESSEE...

...SUMMARY...
Scattered severe thunderstorms are possible this afternoon over New
York into southern Vermont with damaging gusts and perhaps a tornado
or two the primary threats. Large to very large hail is possible
with stronger storms over the northern half of Arkansas.

...Ozark Plateau into the Mid-South...
Recent visible satellite imagery shows some ACCAS across
south-central MO, indicative of low/mid-level warm advection amid
the steep lapse rate environment in place. These steep lapse rates
are forecast to continue spread eastward, while low-level moisture
advection brings low 60s dewpoints northeastward into the region as
well. This will result in a moderate to strongly buoyant airmass
(i.e. MLCAPE from 1500 to 2000 J/kg) by the early afternoon.
Additionally, moderate mid to high level flow will remain in place,
resulting in long hodographs and overall environmental conditions
that are very favorable for supercells capable of large to very
large hail. Latest guidance continues the earlier trends of
developing storms in this area, which match observational
expectations as well. Large to very large hail (1 to 3 inches in
diameter) is possible with any updrafts that mature into supercells.
Low-level flow is weak, keeping tornado probability low but none
zero. Given the modest pocket of mid-level dry air present,
supercells will likely become outflow dominant with time,
supporting the potential for damaging gusts across the region
(particular eastern areas) as well.

...NY/VT/NH southeastward into the central Appalachians...
Recent surface analysis places a low over the eastern
Ontario/southern Quebec border vicinity, with modest surface
troughing extending southeastward from this low across central Lower
MI. Airmass across much of NY is characterized by dewpoints in the
low 60s. Dewpoints should stay in the low 60s throughout the day
despite modest mixing amid diurnal heating. This should result in
airmass destabilization ahead of the modest surface trough, with a
general increase in large-scale ascent beginning during the
afternoon as well. Little to no convective inhibition is
anticipated, supporting the potential for more cellular development
over the warm sector initially, before a more expansive convective
line develops along the eastward-progressing surface trough. Ample
mid to high-level flow will favor storm organization, including a
risk for large hail and a tornado with the more intense discrete
cells. The wind risk will tend to focus with linear structures that
evolve over time. An isolated threat for wind damage and perhaps
hail will extend southward into PA/WV and the Cumberland Plateau,
where a few stronger storms may yield those hazards.

...Edwards Plateau into the TX Big Country and western north TX...
A strongly buoyant and weakly capped airmass is expected to develop
along the dryline extending southwestward from western OK through
the Edwards Plateau. Although neutral to weak shortwave ridging is
expected throughout much of the morning into the late afternoon,
some limited ascent (associated with a weak shortwave trough moving
out of northern Mexico) may begin to spread across the dryline by
early evening. This combined with dryline circulations may be enough
to initiate isolated to widely scattered thunderstorms. Low-level
flow will be weak, but moderate to strong westerly flow aloft will
result in wind profiles very favorable for supercells capable of
large to very large hail. Any storms that develop should weaken
quickly with the onset of nocturnal cooling.

..Mosier/Squitieri.. 04/16/2026

$$

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ACUS01 KWNS 162002
SWODY1
SPC AC 162000

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0300 PM CDT Thu Apr 16 2026

Valid 162000Z - 171200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS NEW YORK
INTO SOUTHERN VERMONT...AND THE OZARKS INTO THE MID-SOUTH...

...SUMMARY...
Scattered severe thunderstorms are possible this afternoon over New
York into southern Vermont with damaging gusts and perhaps a tornado
or two the primary threats. Very large hail and severe gusts are
possible with the stronger storms over the Ozarks into the
Mid-South.

...20Z Update...
The SLGT in the Ozarks/Mid-South was expanded northward into central
MO, where an isolated supercell with a risk of very large hail and
damaging gusts has emerged along the northern periphery of a remnant
cold pool. Farther south within Severe Thunderstorm Watch 127,
several discrete/splitting supercells continue to pose a risk of
very large hail (recent report of 2.75 inches) and locally damaging
wind gusts. With time, this activity may congeal into a loosely
organized cluster, with an increasing risk of damaging wind gusts.
The MRGL risk was also expanded slightly westward into southwest OK,
where boundary-layer cumulus is gradually deepening. Any isolated
storms that can form here will pose a risk of large to very large
hail and severe downbursts. Finally, the MRGL was expanded slightly
westward in southwest TX toward Fort Stockton. While convective
initiation is still in question here, deepening boundary-layer
cumulus along the higher terrain could result in an isolated storm
or two, with a risk of very large hail.

..Weinman.. 04/16/2026

.PREV DISCUSSION... /ISSUED 1124 AM CDT Thu Apr 16 2026/

...Ozark Plateau into the Mid-South...
Recent visible satellite imagery shows some ACCAS across
south-central MO, indicative of low/mid-level warm advection amid
the steep lapse rate environment in place. These steep lapse rates
are forecast to continue spread eastward, while low-level moisture
advection brings low 60s dewpoints northeastward into the region as
well. This will result in a moderate to strongly buoyant airmass
(i.e. MLCAPE from 1500 to 2000 J/kg) by the early afternoon.
Additionally, moderate mid to high level flow will remain in place,
resulting in long hodographs and overall environmental conditions
that are very favorable for supercells capable of large to very
large hail. Latest guidance continues the earlier trends of
developing storms in this area, which match observational
expectations as well. Large to very large hail (1 to 3 inches in
diameter) is possible with any updrafts that mature into supercells.
Low-level flow is weak, keeping tornado probability low but none
zero. Given the modest pocket of mid-level dry air present,
supercells will likely become outflow dominant with time,
supporting the potential for damaging gusts across the region
(particular eastern areas) as well.

...NY/VT/NH southeastward into the central Appalachians...
Recent surface analysis places a low over the eastern
Ontario/southern Quebec border vicinity, with modest surface
troughing extending southeastward from this low across central Lower
MI. Airmass across much of NY is characterized by dewpoints in the
low 60s. Dewpoints should stay in the low 60s throughout the day
despite modest mixing amid diurnal heating. This should result in
airmass destabilization ahead of the modest surface trough, with a
general increase in large-scale ascent beginning during the
afternoon as well. Little to no convective inhibition is
anticipated, supporting the potential for more cellular development
over the warm sector initially, before a more expansive convective
line develops along the eastward-progressing surface trough. Ample
mid to high-level flow will favor storm organization, including a
risk for large hail and a tornado with the more intense discrete
cells. The wind risk will tend to focus with linear structures that
evolve over time. An isolated threat for wind damage and perhaps
hail will extend southward into PA/WV and the Cumberland Plateau,
where a few stronger storms may yield those hazards.

...Edwards Plateau into the TX Big Country and western north TX...
A strongly buoyant and weakly capped airmass is expected to develop
along the dryline extending southwestward from western OK through
the Edwards Plateau. Although neutral to weak shortwave ridging is
expected throughout much of the morning into the late afternoon,
some limited ascent (associated with a weak shortwave trough moving
out of northern Mexico) may begin to spread across the dryline by
early evening. This combined with dryline circulations may be enough
to initiate isolated to widely scattered thunderstorms. Low-level
flow will be weak, but moderate to strong westerly flow aloft will
result in wind profiles very favorable for supercells capable of
large to very large hail. Any storms that develop should weaken
quickly with the onset of nocturnal cooling.

$$

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ACUS01 KWNS 170101
SWODY1
SPC AC 170059

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0759 PM CDT Thu Apr 16 2026

Valid 170100Z - 171200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS EVENING
ACROSS PARTS OF EASTERN NEW YORK INTO WESTERN NEW ENGLAND...PARTS OF
THE OZARK PLATEAU INTO MID SOUTH...AND THE PECOS VALLEY/RIO GRANDE
VALLEY VICINITY...

...SUMMARY...
Widely scattered areas of scattered strong to severe thunderstorm
development are expected to generally wane through mid to late
evening.

...01Z Update...

...Parts of Upstate New York into western New England...
Forcing for ascent accompanying a weak frontal wave is maintaining
an area of scattered stronger storms now overspreading areas to the
northwest of Albany NY, in the presence of strong deep-layer shear.
Instability sampled in the evening sounding from Albany is rather
weak, but profiles might still be supportive of at least some risk
for localized severe wind and hail into mid/late evening as forcing
overspreads parts of southern Vermont, New Hampshire and adjacent
Maine.

...Ozark Plateau into Mid South...
The primary east-southeastward propagating organized storm cluster
appears to be in the process of weakening, as southeasterly near
surface updraft inflow across middle Tennessee becomes less
unstable. However, renewed thunderstorm development persists along
and to the cool side of the trailing convective outflow across the
Missouri Bootheel vicinity, with additional attempts along a diffuse
zone of differential surface heating extending westward across
northern Arkansas. This is occurring beneath warming and more
strongly capping lower/mid-tropospheric air, but given inflow of
potentially sizable CAPE, in the presence of moderate westerly
shear, there remains at least some risk for supercell development
capable of producing large hail this evening.

...West Texas...
Potential for sustained severe thunderstorm development appears low
along the retreating dryline across parts of northwest Texas into
the South Plains overnight.

..Kerr.. 04/17/2026

$$

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ACUS01 KWNS 170602
SWODY1
SPC AC 170600

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0100 AM CDT Fri Apr 17 2026

Valid 171200Z - 181200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON
INTO TONIGHT ACROSS PARTS CENTRAL AND SOUTHWESTERN WISCONSIN...FAR
SOUTHEASTERN MINNESOTA...EASTERN IOWA...MUCH OF NORTHERN AND CENTRAL
ILLINOIS...NORTHERN AND CENTRAL MISSOURI...EASTERN AND SOUTHERN
KANSAS...AND NORTHERN OKLAHOMA...

...SUMMARY...
Widespread strong to severe thunderstorm development appears
possible today into tonight across parts of the Upper Midwest
southward across the lower Missouri Valley into central Great
Plains. Initially this may be accompanied by a risk for large hail
and a few strong tornadoes, before damaging wind gusts become the
most prominent hazard by this evening.

...Discussion...
A couple of notable short wave perturbations have emerged from
splitting larger-scale mid-level troughing now overspreading the
northern Rockies and Great Basin. One, including a remnant embedded
cyclonic circulation, is beginning to accelerate east-northeastward
into and across the central Canadian/U.S. border vicinity. The
other is still digging into the eastern Great Basin, but forecast to
turn across the Wyoming/Colorado Rockies during the day, before
shearing northeastward toward the Upper Midwest. It appears that
this will be preceded by several lower amplitude impulses already
emanating from the subtropical eastern Pacific.

In lower-levels, a significant cold front is already surging
southward to the lee of the northern Rockies and forecast to advance
across much of the remainder of the northern Great Plains by 12Z
this morning. Models indicate that significant cyclogenesis may
subsequently ensue northwest/north of Lake Superior toward James Bay
later today through tonight. At the same time, it appears that a
secondary frontal wave will migrate northeast of the mid Missouri
Valley through the Upper Midwest/Great Lakes vicinity. Another lee
cyclone may attempt to form near/north of the Texas/Oklahoma
Panhandle vicinity, but probably will be overtaken by the southward
surging cold front before migrating out of the high plains.

The northward advection of relatively moist low-level air is ongoing
from the southern into central Great Plains and lower Missouri
Valley, and forecast to continue spreading northward within a
pre-cold frontal plume through portions of the Upper Midwest/Great
Lakes region by this afternoon. Beneath steep lapse rates, this may
contribute to sizable mixed-layer CAPE within a corridor from the
east central Great Plains through the mid/upper Mississippi Valley
by this afternoon.

There is notable spread among the various model output concerning
most of these developments, which may have a significant impact on
the convective evolution and associated severe weather potential
today through tonight. However, potential exists for widespread
convective development capable of producing damaging surface gusts,
large hail and a couple of strong tornadoes.

...Upper Mississippi Valley/Midwest vicinity...
It appears that a corridor of stronger surface pressure falls may
shift from western Iowa north-northeastward through western
Wisconsin by early this afternoon, accompanied by substantive
boundary-layer destabilization and strengthening southerly low-level
wind fields with enlarging hodographs. Based on the latest model
output, including convection allowing guidance, it appears that this
may contribute to a window of opportunity for discrete supercell
development within an environment potentially conducive to strong
tornadoes, before activity grows upscale and eventually outpaces the northeastward boundary-layer destabilization.

...Central Great Plains through middle Mississippi Valley/Midwest...

Uncertainty lingers concerning how quickly the surface cold front
will tend to undercut a developing corridor of stronger pre-frontal
surface heating and destabilization, particularly across the central
into southern Great Plains. However, by early this afternoon, this
corridor appears likely to develop along an axis from south central
Kansas toward northwestern Missouri, providing a focus for rapidly
developing storms including supercells. Initially this may include
hail exceeding 2 inches in diameter, and potential for a few
tornadoes before convection grows upscale, spreads east of the axis
of maximum instability and also become undercut by the front.

Perhaps aided by forcing associated with one of the perturbations
emerging from lower latitudes, there appears a signal in model
output that the upscale growing convection may eventually become
better organized with one or two notable mesoscale convective
vortices evolving while spreading ahead of the front across and
northeast of the lower Missouri Valley late this afternoon and
evening. Downward mixing of strengthening rear-inflow, within a
sheared ambient southwesterly deep-layer mean flow already on the
order of 35-40 kt, widespread strong to severe wind gusts appear
possible, with strongest gusts and/or perhaps brief tornadoes
accompanying evolving mesovortices along the gust front.

The cold front/dryline intersection may become another focus for
discrete supercell development across parts of south central Kansas
into adjacent northwestern Oklahoma by late afternoon. However, the
extent of the associated severe weather potential will depend on how
quickly this activity is overtaken by the cold front.

..Kerr/Lyons.. 04/17/2026

$$

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ACUS01 KWNS 171240
SWODY1
SPC AC 171239

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0739 AM CDT Fri Apr 17 2026

Valid 171300Z - 181200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM PARTS OF
THE UPPER AND MID MISSISSIPPI VALLEY SOUTHWESTWARD INTO KANSAS AND
OKLAHOMA...

...SUMMARY...
Numerous severe thunderstorms are likely this afternoon into tonight
across parts of the Upper Midwest southward across the lower
Missouri Valley into central Great Plains. Initially this may be
accompanied by a risk for large to giant hail and a few strong
tornadoes, before severe wind gusts 60 to 90 mph become the
most prominent hazard by this evening.

...Synopsis...
Surface analysis this morning depicts a front bisecting MN north to
south to a low near the NE-IA-SD border, with the front extending
southwestward into the central High Plains. Water-vapor imagery
shows a prominent upper trough near the MT-ND border
south-southwestward into eastern UT. A belt of increasingly strong southwesterly 500-mb flow will overspread a destabilizing warm
sector today as the upper trough eventually reaches the Upper
Midwest and central Great Plains late tonight. Concurrently, the aforementioned cyclone will develop northeast to Lake Superior as a
warm front over IA advances northward into the western Great Lakes.
Meanwhile, the cold front will sweep southeast reaching the central
Great Lakes southwestward into the southern Great Plains by early
Saturday.

...Upper and Mid Mississippi Valley...
A northward expanding warm/moist sector on the nose of a 50+ kt
southerly LLJ will continue to destabilize as large-scale ascent
approaches from the west. A large-hail threat may develop this
morning with developing convection across southern MN (see
forthcoming MCD #472 for short-term details). Heating and advection
of 60s deg F surface dewpoints beneath steep mid-level lapse rates
will support the development of a moderately to very unstable
airmass from IA-IL northward into the upper MS Valley to the east of
the front and southeast of the low. Upwards of 1500-3000 J/kg
MLCAPE is forecast immediately ahead of the front with strengthening
flow aloft, strongly favoring organized storms, including
supercells. Recent model guidance continues to show the development
of discrete supercells later this afternoon ahead of the front over
parts of central/northern WI near the low, and farther south in the
vicinity of eastern IA into adjacent portions of WI/northwest IL.
All hazards will be possible with this potential activity, including
the possibility for an intense tornado. Large to giant hail will be
possible with supercells. Other storms likely to evolve quickly
into a band of severe thunderstorms will develop farther west and
push east coincident with the front. Damaging wind gusts will tend
to become more prevalent during the evening with linear storm modes.
Some tornado risk may continue into the evening as maturing bands of
storms yield a threat for bowing segments and embedded mesovortices,
before this activity gradually diminishes late as it moves east into
IN/Lower MI late.

...KS-OK eastward into the lower MO Valley...
Continued moistening and heating of an airmass to the east of a
dryline/cold front and associated triple point will lead to a very
unstable airmass from OK into KS by early to mid afternoon. A
capping inversion will likely inhibit storm development until mid
afternoon near the front. Initial storm development will likely be supercellular near the triple point before a more extensive band of
cellular storms develops along the boundary. Both a supercell and
QLCS tornado risk is apparent given the appreciably large
CAPE/shear. A coalescing of cold pools and intensification of a
squall line with embedded surges and bowing segments may result in
focused swaths of more intense severe gusts (i.e., locally 75-90
mph) from south-central and eastern KS into west-central MO.
Farther south, a more conditional setup south of the triple point
along the dryline is expected. Large to giant hail could accompany
any mature/sustained supercell along with a tornado risk.
Eventually the front will sweep southeastward with a convective line
yielding a risk for wind/hail.

..Smith/Dean.. 04/17/2026

$$

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ACUS01 KWNS 171637
SWODY1
SPC AC 171635

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1135 AM CDT Fri Apr 17 2026

Valid 171630Z - 181200Z

...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS FROM FAR
NORTHWEST OKLAHOMA THROUGH CENTRAL AND EASTERN KANSAS INTO
WEST-CENTRAL MISSOURI...

...SUMMARY...
Numerous severe thunderstorms are likely this afternoon into tonight
across parts of the Upper Midwest southward across the lower
Missouri Valley and central/southern Great Plains. Initially this
may be accompanied by a risk for large to giant hail and a few
strong tornadoes, before severe wind gusts of 60 to 90 mph become
the most prominent hazard by this evening.

...Synopsis...
Recent surface analysis places a low over south-central MN, with a
cold front extending southwestward to another low over central KS. A
warm front also extends southwestward from the MN low through far
southwest MN and far northern IL into central IN. This warm front is
demarcated well by the 56 deg F isodrosotherm. Farther south, a
dryline extends from the triple point KS low back southwestward
through the TX Panhandle and into far southeast NM. A broad, moist
warm sector exists to the east of the cold front and dryline,
characterized largely by dewpoints in the low to mid 60s.

A well-defined shortwave trough is apparent on satellite imagery,
extending from southern Saskatchewan back southwestward into the
eastern Great Basin. This wave is forecast to continue eastward,
with a attendant increase in the mid-level flow across much of the
Plains and Upper/Mid MS Valley. The cold front will surge eastward/southeastward in response to this wave as well, interacting
with the warm sector to support numerous strong to severe
thunderstorms from parts of the Upper Midwest southward across the
lower Missouri Valley into southern Plains.

...Upper/Mid MS Valley...
Moderate to strong low-level moisture advection is expected across
the Upper MS Valley today as the surface low mentioned in the
synopsis progresses northeastward, with an attendant northward shift
of the warm front as well. The risk across this region may evolve in
several phases, beginning with the elevated thunderstorms currently
ongoing across northwest WI. This storms will likely continue
northeastward, posing a risk for severe hail and isolated damaging
gusts. Additional development is possible northwest of this activity
along the occluded front, with some hail possible here as well.

Farther south, the northeastward advecting low-level moisture
coupled with strong heating and steep lapse rates will result in a
strongly unstable airmass along and just south of the warm front by
the early afternoon. Storm initiation is anticipated within this
open warm sector by early afternoon, forced by a mix of warm-air
advection, low-level confluence, and subtly increasing large-scale
ascent. This activity should be ahead of the front and initially
discrete. The overall parameter space will be characterized by
strong to very strong buoyancy, moderate deep-layer vertical shear,
and strong low-level helicity. Supercells capable of all hazards are
expected, including large to very large (i.e. 3"+ hail), strong to
intense tornadoes, and severe wind gusts. Storm interactions are
expected to strongly influence the tornado risk, with the initially
discrete mode likely becoming messy quickly.

Farther west, other storms are likely to evolve quickly along the
front, developing into a band of severe thunderstorms that will push
east coincident with the front. Damaging wind gusts will tend to
become more prevalent during the evening with linear storm modes.
Some tornado risk may continue into the evening as maturing bands of
storms yield a threat for bowing segments and embedded mesovortices,
before this activity gradually diminishes late as it moves east into
IN/Lower MI late.

...KS/OK/MO...
A very unstable airmass is expected to develop along and ahead of
the triple point over south-central KS an associated cold front and
dryline. Strong low-level convergence will likely lead to initial
storm development near the triple point. This initial activity will
be supercellular and capable of very large to giant hail (over
3-3.5" in diameter). Highest coverage of very large hail is expected
over from far northwest OK into south-central KS. Strong downdrafts
(60 to 80 mph) are possible as well. With a largely
boundary-parallel orientation to the deep-layer shear, the tornado
risk appears relatively lower. However, given the supercell mode and
potential interactions with outflow, a low-probability tornado risk
remains. A more north-south configuration to the dryline supports a
conditional tornado risk into far northwest TX.

With time, upscale growth and the development of a
forward-propagating MCS is anticipated across central and eastern
KS. Very strong gusts (80+ mph) are possible with this MCS.
Additionally, some QLCS tornado risk will exist within this line as
long as it stays ahead of the surging cold front. The front will
continue sweeping southeastward, with storms along this boundary
yielding a risk for wind/hail.

..Mosier/Chalmers.. 04/17/2026

$$

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ACUS01 KWNS 171955
SWODY1
SPC AC 171953

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0253 PM CDT Fri Apr 17 2026

Valid 172000Z - 181200Z

...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS FROM FAR
NORTHWEST OKLAHOMA THROUGH CENTRAL AND EASTERN KANSAS INTO
WEST-CENTRAL MISSOURI...

...SUMMARY...
Numerous severe thunderstorms are likely this afternoon into tonight
across parts of the Upper Midwest southward across the lower
Missouri Valley and central/southern Great Plains. Initially this
may be accompanied by a risk for large to giant hail and a few
strong tornadoes, before severe wind gusts of 60 to 90 mph become
the most prominent hazard by this evening.

...20Z Update...
Severe probabilities have been adjusted to account for progression
of the cold front this afternoon. The remainder of the forecast is
unchanged. See MD 475 for short-term details of evolving tornado
risk along the Illinois/Wisconsin border.

..Wendt.. 04/17/2026

.PREV DISCUSSION... /ISSUED 1203 PM CDT Fri Apr 17 2026/

...Synopsis...
Recent surface analysis places a low over south-central MN, with a
cold front extending southwestward to another low over central KS. A
warm front also extends southwestward from the MN low through far
southwest MN and far northern IL into central IN. This warm front is
demarcated well by the 56 deg F isodrosotherm. Farther south, a
dryline extends from the triple point KS low back southwestward
through the TX Panhandle and into far southeast NM. A broad, moist
warm sector exists to the east of the cold front and dryline,
characterized largely by dewpoints in the low to mid 60s.

A well-defined shortwave trough is apparent on satellite imagery,
extending from southern Saskatchewan back southwestward into the
eastern Great Basin. This wave is forecast to continue eastward,
with a attendant increase in the mid-level flow across much of the
Plains and Upper/Mid MS Valley. The cold front will surge eastward/southeastward in response to this wave as well, interacting
with the warm sector to support numerous strong to severe
thunderstorms from parts of the Upper Midwest southward across the
lower Missouri Valley into southern Plains.

...Upper/Mid MS Valley...
Moderate to strong low-level moisture advection is expected across
the Upper MS Valley today as the surface low mentioned in the
synopsis progresses northeastward, with an attendant northward shift
of the warm front as well. The risk across this region may evolve in
several phases, beginning with the elevated thunderstorms currently
ongoing across northwest WI. This storms will likely continue
northeastward, posing a risk for severe hail and isolated damaging
gusts. Additional development is possible northwest of this activity
along the occluded front, with some hail possible here as well.

Farther south, the northeastward advecting low-level moisture
coupled with strong heating and steep lapse rates will result in a
strongly unstable airmass along and just south of the warm front by
the early afternoon. Storm initiation is anticipated within this
open warm sector by early afternoon, forced by a mix of warm-air
advection, low-level confluence, and subtly increasing large-scale
ascent. This activity should be ahead of the front and initially
discrete. The overall parameter space will be characterized by
strong to very strong buoyancy, moderate deep-layer vertical shear,
and strong low-level helicity. Supercells capable of all hazards are
expected, including large to very large (i.e. 3"+ hail), strong to
intense tornadoes, and severe wind gusts. Storm interactions are
expected to strongly influence the tornado risk, with the initially
discrete mode likely becoming messy quickly.

Farther west, other storms are likely to evolve quickly along the
front, developing into a band of severe thunderstorms that will push
east coincident with the front. Damaging wind gusts will tend to
become more prevalent during the evening with linear storm modes.
Some tornado risk may continue into the evening as maturing bands of
storms yield a threat for bowing segments and embedded mesovortices,
before this activity gradually diminishes late as it moves east into
IN/Lower MI late.

...KS/OK/MO...
A very unstable airmass is expected to develop along and ahead of
the triple point over south-central KS an associated cold front and
dryline. Strong low-level convergence will likely lead to initial
storm development near the triple point. This initial activity will
be supercellular and capable of very large to giant hail (over
3-3.5" in diameter). Highest coverage of very large hail is expected
over from far northwest OK into south-central KS. Strong downdrafts
(60 to 80 mph) are possible as well. With a largely
boundary-parallel orientation to the deep-layer shear, the tornado
risk appears relatively lower. However, given the supercell mode and
potential interactions with outflow, a low-probability tornado risk
remains. A more north-south configuration to the dryline supports a
conditional tornado risk into far northwest TX.

With time, upscale growth and the development of a
forward-propagating MCS is anticipated across central and eastern
KS. Very strong gusts (80+ mph) are possible with this MCS.
Additionally, some QLCS tornado risk will exist within this line as
long as it stays ahead of the surging cold front. The front will
continue sweeping southeastward, with storms along this boundary
yielding a risk for wind/hail.

$$

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ACUS01 KWNS 180101
SWODY1
SPC AC 180059

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0759 PM CDT Fri Apr 17 2026

Valid 180100Z - 181200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER MUCH OF
ILLINOIS INTO NORTHEAST MISSOURI...AND OVER NORTHERN OKLAHOMA...

...SUMMARY...
Damaging storms producing wind, hail and isolated tornadoes remain
possible this evening from Illinois into Oklahoma.

...WI/MI into IL and MO...
Supercells have largely merged into a broken line of assorted bows
from far southeast WI across much of northern into western IL and
trailing into northeast MO. The 00Z ILX sounding shows steep lapse
rates aloft and large deep-layer shear, as well as veering winds
with height. Low-level SRH will remain favorable for rotation to
develop at least briefly anywhere within the line, with damaging
winds the most likely threat. Storms have recently become better
organized over central MO, and this activity may affect the St.
Louis area later tonight. For lower MI into northern IN, the
organized line of storms to the west along with a 60 kt low-level
jet suggest at least isolated severe gusts may occur overnight
despite lesser instability.

For more information about Illinois, see mesoscale discussion 484.

...OK...Southeast KS...southwest MO...northwest AR...
Scattered severe cells persist near and north of the cold front
across much of northern OK and extending into southeast KS. Although
the undercutting cold air will likely mitigate wind potential, steep
lapse rates aloft along with ample deep-layer shear will continue to
favor hail. Storm coverage may be more isolated into southwest OK
later tonight, but the environment remains quite favorable for large
hail.

One corridor for possible damaging wind or even a tornado is over
northeast OK into southwest MO. Here, the front is not surging as
fast, and storms over Osage county are already oriented more
favorably N-S relative to the deep-layer shear. A southwest
low-level jet near 50 kt will further support low-level rotation.

..Jewell.. 04/18/2026

$$

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ACUS01 KWNS 180454
SWODY1
SPC AC 180453

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1153 PM CDT Fri Apr 17 2026

Valid 181200Z - 191200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE
UPPER OHIO VALLEY TO THE APPALACHIANS...

...SUMMARY...
Scattered strong to severe thunderstorms capable of damaging winds
and hail will be possible on Saturday across the upper Ohio Valley
and central Appalachians. Isolated severe hail is also possible
across parts of central Texas.

...Synopsis...
A large upper trough with elongated leading speed max will sweep
across the Great Lakes and OH Valley during the day and into the
Appalachians by Sunday morning. Meanwhile, moderate westerlies aloft
will persist across TX with the aid of a subtropical jet.

At the surface, a cold front will move across OH and KY through
early afternoon, and into western NY, PA, and WV late in the day.
This front will also extend far southwestward toward the
northwestern Gulf Coast and into far southern TX. Ahead of the
front, a narrow plume of 50s to lower 60s F dewpoints will exist as
far north as OH and PA, with more robust moisture into TX with upper
60s F dewpoints.

...Upper Ohio Valley/Appalachians...
A remnant line of showers and thunderstorms is expected to persist
near the cold front this morning as it moves across the OH Valley
and toward the lower Great Lakes. Daytime heating will help
destabilize the air mass ahead of this activity, and storm
rejuvenation is expected after 18Z from near Lake Erie into eastern
KY. These storms will mature in the 21-00Z timeframe, affecting
eastern OH, WV, and into PA and possibly southwest NY.

Substantial southwest flow aloft will help to push these storms
quickly east/northeast across the region, and deep-layer shear may
favor scattered cells initially. Marginal hail will be possible,
along with locally strong gusts, especially as storm mode becomes
linear and peak heating has been achieved. Given the narrow
instability axis, storms should wane after sunset.

...South-Central Texas...
Scattered showers and elevated thunderstorms are expected throughout
much of the day as the cold front rapidly undercuts a moist and
unstable air mass. Forecast soundings show MUCAPE parcels rooted in
the 850-700 mb layer, with effective deep-layer shear of 50-60 kt.
Initial activity may develop over central TX during the morning and
through midday, with additional new elevated development translating
southward as the front continually lifts the moist air mass. A few
hail reports at or above 1.00" will be possible.

..Jewell/Moore.. 04/18/2026

$$

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ACUS01 KWNS 181233
SWODY1
SPC AC 181232

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0732 AM CDT Sat Apr 18 2026

Valid 181300Z - 191200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE
UPPER OHIO VALLEY TO THE APPALACHIANS...

...SUMMARY...
Scattered strong to severe thunderstorms capable mainly of damaging
winds will be possible today across the upper Ohio Valley and
central Appalachians.

...Synopsis...
Water-vapor imagery this morning shows a large-scale upper trough
over the Upper Midwest into the south-central Plains. An elongated
mid-level vorticity lobe and associated speed max will quickly move
eastward across the Midwest today and reach the Lower Great Lakes
and upper OH Valley late tonight. Farther south, a belt of strong west-southwesterly flow associated with a subtropical jet will
reside over TX.

A cold front extending from a low near James Bay southward through
the Great Lakes and into TX will continue to push east and southeast
through the period. Convective outflow over the OH Valley to the
east of the front will eventually be overtaken by the front later
today as a band of showers/thunderstorms develops over the upper OH
Valley by early afternoon.

...OH Valley into the Appalachians...
Some heating combined with a gradually moistening airmass (55-60 deg
F surface dewpoints) will result in weak destabilization by midday
as convective development ensues near the preceding outflow/wind
shift and front. Ample mid to high-level flow will aid in some
potential for storm organization, mainly in the form of a few
stronger cells and linear bands. Widely scattered strong to severe
gusts capable of wind damage will likely be the primary hazard, but
an isolated risk for hail or a brief tornado is possible with the
strongest cells. This activity will likely weaken by early evening
as it encounters a slightly drier and less unstable airmass with
east extent.

...Central Texas...
Scattered showers and elevated thunderstorms are expected throughout
much of the day as the cold front rapidly undercuts a moist and
unstable air mass. The 12 UTC Del Rio, TX raob shows an 8.2 deg
C/km 700-500 mb lapse rate. Forecast soundings show MUCAPE parcels
rooted in the 850-700 mb layer, with effective deep-layer shear of
50-60 kt. Although an isolated risk for large hail appears to be
the main hazard with the stronger cells, there has been some
indication that a localized risk for severe gusts could accompany
the strongest cores. For short-term details regarding a risk for
hail/wind with a few stronger thunderstorms this morning extending
from the Concho Valley east-northeast towards DFW, reference MCD
#490.

..Smith/Dean.. 04/18/2026

$$

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ACUS01 KWNS 181605
SWODY1
SPC AC 181603

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1103 AM CDT Sat Apr 18 2026

Valid 181630Z - 191200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON
ACROSS PARTS OF THE UPPER OHIO VALLEY AND LOWER GREAT LAKES
REGION....

...SUMMARY...
Widely scattered strong to severe thunderstorms capable mainly of
damaging winds will be possible today across the Upper Ohio Valley
and Lower Great Lakes.

...Upper OH Valley...
Latest surface analysis shows a cold front pushing eastward across
western OH, associated with a band of widespread clouds and light precipitation. Mostly clear skies are present ahead of the front,
where temperatures are warming through the 70s. This will lead to a
corridor of marginal afternoon instability and the potential for
scattered thunderstorm intensification along the front. Forecast
soundings show strong mid-level winds and steep low-level lapse
rates, supportive of strong downdrafts in any vigorous convection.
However, CAM guidance is consistent in showing very few
organized/strong storms through the day. Will maintain the SLGT
risk for the conditional risk of a few damaging wind events, but
with limited confidence.

...TX...
Isolated intense thunderstorms have been ongoing this morning in the post-frontal regime across central TX. These storms have produced
hail and gusty winds for several hours. It appears likely that this
scenario will shift eastward and weaken early this afternoon as the
primary upper jet moves into AR and away from the region, but will
maintain the MRGL risk area for a few more hours and extend it into
parts of AR/LA.

..Hart/Chalmers.. 04/18/2026

$$

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ACUS01 KWNS 182006
SWODY1
SPC AC 182005

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0305 PM CDT Sat Apr 18 2026

Valid 182000Z - 191200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS WITHIN THE
CENTRAL APPALACHIANS INTO THE UPPER OHIO VALLEY VICINITY...AND PARTS
OF CENTRAL TEXAS...

...SUMMARY...
Isolated marginally severe hail is possible in portions of central
Texas. Isolated damaging winds remain possible from the central
Appalachians into the Upper Ohio Valley vicinity.

...20Z Update...
Based on observational trends 15% wind probabilities were removed
from the Upper Ohio Valley vicinity. Wind gusts along with weak,
shallow convection (with little lightning) have generally been in
the 30 kt range with isolated cases of low 40 kt gusts. Isolated
wind damage remains possible, but a more organized threat is not
expected given weak buoyancy downstream. Elsewhere, marginally
severe hail remains possible with isolated, elevated convection in
central Texas.

..Wendt.. 04/18/2026

.PREV DISCUSSION... /ISSUED 1103 AM CDT Sat Apr 18 2026/

...Upper OH Valley...
Latest surface analysis shows a cold front pushing eastward across
western OH, associated with a band of widespread clouds and light precipitation. Mostly clear skies are present ahead of the front,
where temperatures are warming through the 70s. This will lead to a
corridor of marginal afternoon instability and the potential for
scattered thunderstorm intensification along the front. Forecast
soundings show strong mid-level winds and steep low-level lapse
rates, supportive of strong downdrafts in any vigorous convection.
However, CAM guidance is consistent in showing very few
organized/strong storms through the day. Will maintain the SLGT
risk for the conditional risk of a few damaging wind events, but
with limited confidence.

...TX...
Isolated intense thunderstorms have been ongoing this morning in the post-frontal regime across central TX. These storms have produced
hail and gusty winds for several hours. It appears likely that this
scenario will shift eastward and weaken early this afternoon as the
primary upper jet moves into AR and away from the region, but will
maintain the MRGL risk area for a few more hours and extend it into
parts of AR/LA.

$$

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ACUS01 KWNS 190023
SWODY1
SPC AC 190022

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0722 PM CDT Sat Apr 18 2026

Valid 190100Z - 191200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Severe storms are unlikely through tonight.

...Synopsis...
Little thunderstorm activity is currently present near the cold
front moving across NY and PA, with only isolated lightning flashes
across WV into western VA. Given the loss of heating, and already
minimal instability present, severe storms appear unlikely to
develop.

Farther south, scattered storms exist over northern AL near the
front, and north of the boundary from LA into central TX. In both
these areas, instability is weak, and generally should not support a
severe threat as the surface air mass cools.

..Jewell.. 04/19/2026

$$

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ACUS01 KWNS 190519
SWODY1
SPC AC 190517

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1217 AM CDT Sun Apr 19 2026

Valid 191200Z - 201200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Severe thunderstorms are not forecast today.

...Synopsis...
A large upper trough extending from the Great Lakes into the OH and
TN Valleys will move into the northeastern US today, with a weak
upper ridge across the Rockies. This pattern will favor high
pressure over the central and eastern states, stable conditions and
minimal thunderstorm activity. A cold front associated the eastern
trough will be well off the East Coast by midday, with drying
offshore flow. Minimal instability may yield isolated thunderstorms
over eastern Florida, or perhaps across the Rio Grande Valley where
elevated moisture and weak instability will remain atop the surface
cool layer. In any case, severe storms are not forecast.

..Jewell/Moore.. 04/19/2026

$$

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ACUS01 KWNS 191244
SWODY1
SPC AC 191243

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0743 AM CDT Sun Apr 19 2026

Valid 191300Z - 201200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Severe thunderstorms are not forecast today.

...Synopsis...
Water-vapor imagery this morning shows a large-scale upper trough
from James Bay southward through the Great Lakes and TN Valley. The
upper trough will continue to move east and reach the Lower Great
Lakes and East Coast by daybreak Monday. In the low levels, a cold
front will push east of the Carolina coast by early afternoon.
Surface high pressure will influence conditions across the central
and eastern states in wake of the cold front. Weak instability will
yield isolated thunderstorms over parts of the south Florida,
eastern North Carolina, and weak elevated storms over south Texas.

..Smith/Thompson.. 04/19/2026

$$

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ACUS01 KWNS 191601
SWODY1
SPC AC 191559

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1059 AM CDT Sun Apr 19 2026

Valid 191630Z - 201200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Severe thunderstorms are not forecast today.

...Synopsis...
A shortwave trough currently approaching Baja California will
provide increasing large-scale forcing for ascent over Mexico and
south/west TX today. This will lead to scattered thunderstorms
through the period.

Other isolated afternoon thunderstorms are expected ahead of a
frontal band affecting New England and eastern NC, beneath cold air
aloft in the Lower Great Lakes region, and over south FL. In all of
these areas, weak instability and/or limited vertical shear will
preclude a risk of organized severe storms.

..Hart/Bunting.. 04/19/2026

$$

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