AWUS01 KWNH 081826
FFGMPD
FLZ000-090025-

Mesoscale Precipitation Discussion 0084
NWS Weather Prediction Center College Park MD
225 PM EDT Wed Apr 08 2026

Areas affected...Treasure and Gold Coast of Florida

Concerning...Heavy rainfall...Flash flooding possible

Valid 081825Z - 090025Z

SUMMARY...Scattered showers and thunderstorms with a history of
rainfall rates over 2 inches/hour are impacting portions of the
Treasure and Gold Coast of Florida, with increasing concerns for
impacts over sensitive urban areas. Flash flooding is possible
where the cells are the most persistent through the afternoon and
early evening.

DISCUSSION...Persistently moist and relatively unstable low-level
easterly flow continues to focus areas of showers and some
occasional thunderstorms into the Atlantic Coast of Florida. Much
of the activity is aligned with the low-level steering flow and
has been focusing near the offshore Gulf Stream with extensions
westward into areas mainly south of Melbourne and especially areas
just north of Stuart where convection is more concentrated. More
scattered activity is situated farther south down the coast into
the I-95 urban corridor of southeast Florida.

Despite the relatively scattered nature of the coverage, with
southwesterly flow aloft (as opposed to easterly flow in the lower
levels), the extreme directional shear present across Florida is
making an environment favorable for slow-moving and training
storms. Daytime heating is also allowing for instability to
increase, currently ranging from 2,000 J/kg near Miami to near
1,500 J/kg near Melbourne based on SPC Mesoanalysis. Atmospheric
moisture also ranges from 1.7" PWAT near Miami to 1.4" near
Melbourne. Thus, the greatest threat for the heaviest rains are
further south down I-95.

Multiple days of rainfall across all of southern Florida this past
week has sufficiently saturated the soils. Thus, expect much of
any heavy rainfall today to favor increased runoff. Ultimately any
impacts and the magnitudes thereof will be dependent on where any
training cells develop relative to how urban the ground underneath
the cells is. With rates in the strongest cells later this
afternoon expected to potentially reach 3 inches/hour, localized
totals to 6 inches can't be ruled out. This in turn would result
in localized flooding. Regardless, expect that the storms that
will be capable of flash flooding to remain isolated to widely
scattered.

Wegman

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!7reFGpJjrW38AH1Upf3utPD1RP59anTYXGOCvwwonvVJOkizU1tqghWCW4TM6SECp_jb= F2MXRT9fT1GHYMWwAo3DhII$ for graphic product...

ATTN...WFO...MFL...MLB...

ATTN...RFC...ALR...NWC...

LAT...LON 28028067 27988037 26947997 25957994 25598022=20
25498051 25708057 26008045 26288039 26648033=20
26938037 27298050 27528056 27828068=20

=3D =3D =3D
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AWUS01 KWNH 091025
FFGMPD
FLZ000-091500-

Mesoscale Precipitation Discussion 0085
NWS Weather Prediction Center College Park MD
624 AM EDT Thu Apr 09 2026

Areas affected...east-central FL Peninsula

Concerning...Heavy rainfall...Flash flooding possible

Valid 091017Z - 091500Z

Summary...Slow moving showers with possible embedded thunderstorms
are expected to focus isolated areas of heavy rain along the Space
and Treasure coasts through late morning. Localized hourly
rainfall of 2+ inches will be possible with storm totals of 2 to
4+ inches through 15Z, which may result in isolated flash flooding.

Discussion...Regional radar imagery at 10Z showed scattered
showers between southern Brevard County and southern St. Lucie
County. 10.3 micron satellite imagery indicated cloud tops over
land were relatively warm at -20 to -35 C, with an estimated cloud
depth of 9 km AGL based on RAP analysis soundings over the region.
Easterly winds of 20-30 kt in the 925-850 mb layer were oriented
perpendicular to the coast while mid-upper level flow was from the
west at a similar magnitude. This has set up favorable effective
shear profiles for organized cells although 0-8 km AGL mean layer
winds were about 5 kt or less, resulting in slow cell movement. In
addition, the alignment of showers with the low level wind has
also resulted in slow movement of heavy rain cores at times with
recent development near Vero Beach showing signs of a weak MCV
over eastern Indian River County. MRMS-derived and KVRB hourly
rainfall of 2-2.5 inches has been observed with nearly 2 inches of
rain in 32 minutes at KVRB ending 0940Z. Speed and weak
directional convergence near the surface was allowing for the
formation of quasi-transient bands of heavy rain within an
expanding pocket of MLCAPE between 500-1000 J/kg (06Z-10Z SPC
mesoanalyses) over the east coast of FL.

While the future existence of the weak meso-vortex near Vero Beach
is unknown, convergence in the surface to near-surface layer is
expected to continue a threat for slow moving showers with
embedded thunderstorms from Brevard County down to St. Lucie
County over the next 3-5 hours. However, the concentration of
heavy rain is expected to remain limited in spatial extent through
the morning hours. Any areas of flash flooding that develop are
likely to focus across urban and other areas of poor draining,
remaining localized in coverage.

Otto

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!9mIL8BFa2gasaYWoyUi5qRG3Of1RRU_n9PRYp394FRPLoJ3dKXYY6S7SbSiGb2zS-sgD= TGJYn7ZaxolHVDjniKRixg4$ for graphic product...

ATTN...WFO...MLB...

ATTN...RFC...ALR...NWC...

LAT...LON 28608054 27788010 27008004 26998066 27908111=20
28528112=20

=3D =3D =3D
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AWUS01 KWNH 100134
FFGMPD
MOZ000-KSZ000-NEZ000-100730-

Mesoscale Precipitation Discussion 0086
NWS Weather Prediction Center College Park MD
932 PM EDT Thu Apr 09 2026

Areas affected...Northeast KS...West-Central MO

Concerning...Heavy rainfall...Flash flooding possible

Valid 100133Z - 100730Z

SUMMARY...Upscale growth of organizing supercellular convection
into a multi-cell cluster/MCS will promote a localized and
primarily urban flash flood threat going into the overnight hours.

DISCUSSION...The latest radar and GOES-E IR satellite imagery
depict a cluster of supercells along a slow-moving cold front near
the KS/NE border. These storms are undergoing upscale growth, with
supporting factors including fairly strong effective bulk shear of
to 40 to 50 kts and MLCAPE of 1000 to 1500+ J/kg. Over the last
hour, this has favored an expansion of deep, cold convective tops
and intense updrafts.

As the 850 mb low-level jet veers and intensifies to over 40 kts
over the next several hours, low-level convergence will sharpen
along the western and southern flanks of the convective mass. With
storm motions of 15 to 25 kts generally parallel to the mean flow
and the boundary, periods of cell-training and cell-mergers are
expected. This will compensate for modest PWs of about 1.25 inches
and drive potential for high rainfall rates that may reach 1.5 to
2.5 inches/hour within the strongest cores and where any
cell-mergers occur.

While NASA SPoRT 0 to 10 cm soil moisture indicates significant
infiltration capacity in rural northeast KS, the 18Z HREF PMM and
neighborhood probabilities suggest localized 2 to 4 inch totals
are likely. These totals will approach and may locally exceed FFG
values and especially within the more sensitive urban corridors.
Areas downstream including Topeka, Kansas City and St. Joseph may
eventually see this activity later in the night. As such, the
concern over the next several hours, aside from well-defined
severe hazards with large hail, will be a localized and mainly
urban flash flood threat.

Orrison

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!_V7P-J8QajZr8lmjAAmMYppb9LFmhtmko5uyNfAQNigk4X-nlxLjoH4L5j2wU9TvIs0M= nU_APk1NO-Lbst4Tpg4ANoA$ for graphic product...

ATTN...WFO...EAX...GID...ICT...OAX...TOP...

ATTN...RFC...KRF...TUA...NWC...

LAT...LON 40059625 39869477 39589418 38989419 38569493=20
38389618 38599761 38989810 39639790=20

=3D =3D =3D
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AWUS01 KWNH 101901
FFGMPD
OKZ000-110100-

Mesoscale Precipitation Discussion 0087
NWS Weather Prediction Center College Park MD
300 PM EDT Fri Apr 10 2026

Areas affected...North-Central to Northeast OK

Concerning...Heavy rainfall...Flash flooding possible

Valid 101900Z - 110100Z

SUMMARY...Locally training areas of heavy showers and
thunderstorms will pose a threat for some urban flash flooding
going through early this evening.

DISCUSSION...Cooling convective tops are seen in GOES-E IR
satellite imagery becoming aligned in a general west to east
fashion across portions of north-central to northeast OK in close
proximity to a quasi-stationary front. Heavy showers and
thunderstorms are becoming a bit more concentrated with this
activity, and the latest radar trends suggest slow cell-motions
and some increasing cell-training concerns.

The activity is being facilitated by moist and unstable low-level
southwest flow into the boundary with MLCAPE values of as much as
1500 to 2000 J/kg and PWs of 1.2 to 1.4 inches across the region.
Despite relatively modest kinematic wind fields, there is an axis
of moderate moisture convergence in vicinity of the front, and
this coupled with increasing differential heating/instability near
the axis of convection should tend to sustain the convective
threat over the next few hours.

Generally the antecedent conditions are quite dry, with low soil
moisture content, but the rainfall rates with some of the ongoing
activity is already locally near 1.5 inches/hour. This coupled
with the slow cell-motions may favor some short-term totals of 2
to 4+ inches going through early this evening.

An isolated and mainly urban threat of flash flooding will exist
over the next few hours as a result, and this will include areas
from near Stillwater to Tulsa and along with adjacent communities.

Orrison

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!7OMNe7bjzHGDuwRqcrOJ2shcTqUhlC8m8hS1dASOvDqJHGktya8xtEnuVl08ZovWkQ9-= eoQLKiJCVgHcmzqf1PHbDHk$ for graphic product...

ATTN...WFO...OUN...TSA...

ATTN...RFC...TUA...NWC...

LAT...LON 36599485 36349471 35939536 35829684 35999767=20
36369765 36489701 36469622=20

=3D =3D =3D
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AWUS01 KWNH 102142
FFGMPD
TXZ000-110200-

Mesoscale Precipitation Discussion 0088
NWS Weather Prediction Center College Park MD
541 PM EDT Fri Apr 10 2026

Areas affected...Southeast Texas including the Houston
Metropolitan area

Concerning...Heavy rainfall...Flash flooding possible

Valid 102141Z - 110200Z

SUMMARY...Slow-moving, outflow-driven thunderstorms interacting
over highly urbanized areas will be capable of producing localized
rainfall rates of 2+ inches/hour. Isolated totals of 3 to 4 inches
may rapidly overwhelm municipal drainage, making localized flash
flooding possible.

DISCUSSION...Recent radar and satellite trends depict scattered,
slow-moving clusters of thunderstorms developing across southeast
Texas. The thermodynamic environment is characterized by a moist,
weakly convergent low-level flow off the Gulf of America, with
PWATs near 1.75 inches and MLCAPE values around 1500 J/kg. While
deep-layer shear remains weak (effective bulk shear 20-30 kts),
weak upper-level divergence is supplying modest deep-layer ascent,
aiding in some maintenance of robust, high-efficiency updrafts.

Given the weak steering flow, the convective mode is primarily
pulse-type and outflow-dominant. The immediate flash flood threat
will be driven by mesoscale boundary interactions. Regional radar
currently shows multiple outflow boundaries in play?most notably
one positioned southwest of the Houston metro and another near
IAH. As these boundaries interact over the next few hours,
mechanical lift may force rapid, near-stationary convective
development and upscale growth directly over more sensitive urban
locations.

Rainfall rates have already approached 2 inches/hour with the
strongest cells. High-resolution guidance, particularly the HRRR
which has initialized the current convective evolution well,
suggests these boundary collisions will support isolated
additional rainfall totals of 3 to 4 inches through early this
evening. Furthermore, the 12Z HREF highlights 10-30% probabilities
for 3-hour FFG exceedance this over the next several hours. Given
the high impervious surface coverage across the Houston metro,
these rates and accumulations may overwhelm local drainage systems
and bayous, leading to isolated areas of rapid-onset urban flash
flooding.

Orrison

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!8UfP-FaEBTsYZq-U1BJISNdMdxS4kIjqF_7XutdEJFcVHfKrrsDx-b0npcVgfvZAwJZw= 5TdXzeXil7_qMLwkC4AGQLA$ for graphic product...

ATTN...WFO...EWX...FWD...HGX...

ATTN...RFC...FWR...NWC...

LAT...LON 31059623 30659519 30319469 29999457 29479462=20
28919531 28909635 29599753 30359774 30939727=20 =20=20=20=20=20=20=20=20=20=20=20=20

=3D =3D =3D
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AWUS01 KWNH 110515
FFGMPD
MOZ000-IAZ000-KSZ000-NEZ000-111000-

Mesoscale Precipitation Discussion 0089
NWS Weather Prediction Center College Park MD
114 AM EDT Sat Apr 11 2026

Areas affected...northeastern KS into southern/southeastern NE and
the MO Valley

Concerning...Heavy rainfall...Flash flooding possible

Valid 110507Z - 111000Z

SUMMARY...Localized flash flooding will be possible from portions
of northeastern KS into southern/southeastern NE and the MO Valley
through 10Z. Brief training of thunderstorms will be capable of
1-2 in/hr rain rates.

DISCUSSION...Showers and thunderstorms were increasing in coverage
across north-central KS into far southern NE as seen on area radar
imagery through 05Z. The cells were elevated, displaced well north
of a west-east oriented quasi-stationary front in OK, within an
airmass containing 500-1000 J/kg MUCAPE per 05Z SPC mesoanalysis
data. Since 00Z, Southerly 850 mb winds have been strengthening
with 30-40 kt in place at 05Z per VAD wind data from northern OK
into southern NE. PWAT values were estimated to be between 1.0 and
1.3 inches across the central Plains with continued moisture
advection likely to increase PWAT values into the MO River Valley
through the night.

Some additional strengthening of the 850 mb flow into the 40-45 kt
range across KS is expected over the next 3-4 hours and the
approach of a weak shortwave impulse over southwestern KS should
continue an increasing trend in the coverage of elevated
showers/thunderstorms from northeastern KS into
southern/southeastern NE over the next few hours. As 850 mb winds
increase overnight, some veering of the low level flow is also
expected, bringing the low level wind orientation closer to the
mean steering flow from the SW. Given the moisture, instability
and forecast winds, some instances of training are likely to
result in hourly rainfall of 1 to 2 inches. These higher rates
should remain limited in coverage but flash flood guidance is at
or below 2 inches in 3 hours for much of the region, due in part
to locally heavy rainfall over the past 36 hours. Therefore,
localized flash flooding may result overnight with 1 to 3+ inch
total rainfall possible.

Otto

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!48qr4XsdiFtClShi6w-ZrnC2lWuijYOSz66OvZpJ5YDM_U5fNmZMtF-REmLIPl0U20QT= 1Yeb5phRPebNuvpJ0GHXGlw$ for graphic product...

ATTN...WFO...EAX...GID...ICT...OAX...TOP...

ATTN...RFC...KRF...TUA...NWC...

LAT...LON 41329712 41299612 41169573 40809531 40499501=20
40259485 39909472 39469469 39099484 38789510=20
38589566 38619653 39009760 39669878 40339891=20
40899846=20

=3D =3D =3D
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AWUS01 KWNH 110955
FFGMPD
MOZ000-IAZ000-KSZ000-NEZ000-111330-

Mesoscale Precipitation Discussion 0090
NWS Weather Prediction Center College Park MD
554 AM EDT Sat Apr 11 2026

Areas affected...northeastern KS/southeastern NE into southwestern IA/northwestern MO

Concerning...Heavy rainfall...Flash flooding possible

Valid 110953Z - 111330Z

SUMMARY...A localized flash flood threat will linger for another
few hours from northeastern KS/southeastern NE into southwestern IA/northwestern MO. The primary concern will be from
repeating/training of thunderstorms which will be capable of 1 to
2+ in/hr rain rates.

DISCUSSION...A NW to SE axis of thunderstorms was observed on
radar imagery at 0930Z from the KS/NE border near Superior, NE to
near Westmoreland in northeastern KS. The slow moving axis has
been associated with MRMS-derived hourly rainfall of 1 to 2+
inches over the past couple of hours but the axis of thunderstorms
appears to be slowly shifting northeast. 850 mb winds of 3o to 40+
kt continued to overrun a warm front slowly lifting north from
central OK with an axis of elevated convergence helping to focus
the cluster of heavy rain beneath a ridge axis aloft locally
aiding diffluent flow in the upper levels. A subtle shortwave was
also observed on water vapor imagery earlier in the night and is
likely approaching central KS with forecast movement toward the
northeast, around the ridge, helping to support lift.

850 mb wind speed magnitudes have likely peaked and recent RAP
forecasts showed gradual weakening through 15Z following the
diurnal cycle. However, ~25 to 35 kt of SSW 850 mb winds over
eastern KS will continue to overrun the surface boundary to the
south and the weak shortwave impulse approaching central KS from
the southwest will continue to provide ascent from northeastern KS
into the MO River Valley. Instability will be a limiting factor as
current values of MUCAPE between 500-1000 J/kg are forecast to
lower as moisture advection shifts the instability eastward across
the MO River.

The axis of heavy rain will likely translate eastward over the
next few hours with continued periods of training/repeating cells
with 1 to 2+ in/hr rainfall rates. This will continue to pose a
localized threat for flash flooding from northeastern
KS/southeastern NE into northwestern MO and possibly southwestern
IA. Additional rainfall of 1 to 3 inches is expected through 14Z
with locally higher flash flood potential where overlap occurs
with wet antecedent conditions over northeastern KS due to locally
heavy rain over the past 36 hours.

Otto

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!8QQxASh5-vvLIyl0bOPmA5lpyQV8ph24pEYcquvTGWv9coFrhCZ5EnwIYxnrAS6KQ6_k= hg_4xliiOI76F61lkLRs1XE$ for graphic product...

ATTN...WFO...DMX...EAX...GID...OAX...TOP...

ATTN...RFC...KRF...NWC...

LAT...LON 41019522 40889393 40389350 39719368 39169441=20
39049551 39189654 39689754 40029835 40609801=20
40819704=20

=3D =3D =3D
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AWUS01 KWNH 111337
FFGMPD
MOZ000-KSZ000-NEZ000-111636-

Mesoscale Precipitation Discussion 0091
NWS Weather Prediction Center College Park MD
936 AM EDT Sat Apr 11 2026

Areas affected...Northeastern Kansas...Northwest Missouri

Concerning...Heavy rainfall...Flash flooding possible

Valid 111336Z - 111636Z

Summary...Training of thunderstorms containing 1-2"/hr rainfall
rates will maintain the threat of localized flash flooding for
another few hours, primarily over portions of northeastern Kansas.

Discussion...Regional radar this morning continues to track a west
to east axis of training thunderstorms within a slow moving MCS
near the Kansas-Nebraska border. Recent MRMS estimated hourly
rainfall rates have eclipsed 2"/hr at times in the heaviest cells
at times. When combined with the slow net movement of the complex
(Corfidi Vectors are around 10-15 kts), 4-5" of rainfall led to at
least three reports of flash flood impacts in northern Kansas this
morning.

As highlighted earlier, the activity remains tied to a 35-40kt
low-level jet which is bisecting a west-east oriented cold pool
and synoptic front amid locally diffluent flow aloft. Radar
imagery also suggests the presence of a weak MCV embedded in the
complex which could locally enhance ascent in the area. Over the
next few hours, the RAP suggests 30-35 kts of 850 mb inflow
bisecting the west-east boundary could maintain the complex for a
few more hours, even with modest instability in place (~500 J/kg
MUCAPE). Much of the overnight CAM guidance has struggled with the
placement and intensity of this complex. However, the ARW seems to
have a better handle on the current activity and suggests the
training axis could persist for the next few hours. As such, the
threat of localized flash flooding will persist this morning, with
an additional 1-2" of rain possible.

Asherman

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!7JDOHnwHVyoR9jvHIv4Dnizxwzt84oyH6DeI-4eZAhUKsKh7HBFJN6Ci6MbF7c57gFaW= ya8_oxZmjL-r0Fiq-jZ10xE$ for graphic product...

ATTN...WFO...EAX...OAX...TOP...

ATTN...RFC...KRF...NWC...

LAT...LON 40259601 40219520 40019439 39599433 39489490=20
39379618 39389653 39449696 39759714 39979690=20 =20=20=20=20=20=20=20=20=20=20=20=20

=3D =3D =3D
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AWUS01 KWNH 112028
FFGMPD
TXZ000-120226-

Mesoscale Precipitation Discussion 0092
NWS Weather Prediction Center College Park MD
427 PM EDT Sat Apr 11 2026

Areas affected...portions of western TX

Concerning...Heavy rainfall...Flash flooding possible

Valid 112026Z - 120226Z

Summary...Showers and thunderstorms are increasing in coverage and
intensity. Hourly rain amounts up to 2.5" with local totals to 4"
are possible into this evening, which could lead to widely
scattered flash flooding.

Discussion...A region of 850 hPa confluence is slowly moving
across western TX. Convection across the TX Big Bend is sending
out an outflow boundary to the east. Precipitable water values
are ~1.25". An incoming shortwave is moving across northwest
Mexico, enhancing difluence aloft and increasing the effective
bulk shear to 25-45 kts. ML CAPE is 500-2000 J/kg, and rising.

With time, the area of 850 hPa confluence edges eastward across
portions of the TX Big Bend, Trans Pecos, and northwest TX. The
GFS-based Galvez-Davison Index implies that increasing convective
coverage and intensity should maximize in the 00z-03z time frame.=20
The shifting of the low-level confluence axis should keep amounts
from becoming particularly extreme. The available ingredients
suggest that hourly rain amounts up to 2.5" with local totals to
4" would be possible in this environment. Since Flash Flood
Guidance is modest, widely scattered flash flooding impacts are
considered possible. Urban areas and locations with minimal top
soil in western portions of South-Central TX would be most
sensitive to these rainfall rates/amounts.

Roth

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!6S6CodPXk1xunr7JwSe-qfaJRSzvcJUN_gfh9rSEMdEsInWsF0bToaBGQrG4Q__GFerO= bHIbaYGzFZOD7tsUELiUuZM$ for graphic product...

ATTN...WFO...EWX...FWD...LUB...MAF...OUN...SJT...

ATTN...RFC...FWR...TUA...NWC...

LAT...LON 34550074 34309932 33279892 32129929 31020003=20
29800112 29510153 29590244 29080278 28910311=20
29070379 29560431 31090307 33270244=20

=3D =3D =3D
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AWUS01 KWNH 120257
FFGMPD
TXZ000-120715-

Mesoscale Precipitation Discussion 0093
NWS Weather Prediction Center College Park MD
1056 PM EDT Sat Apr 11 2026

Areas affected...portions of the middle Rio Grande Valley into the
Edwards Plateau

Concerning...Heavy rainfall...Flash flooding likely

Valid 120252Z - 120715Z

Summary...Training of thunderstorms is likely to produce areas of
flash flooding from portions of the middle Rio Grande Valley into
the Edwards Plateau over the next 4-5 hours. Peak hourly rainfall
could exceed 2 or 3 inches at times.

Discussion...Regional radar imagery at 0230Z showed a broken line
of strong convection extending from near SJT to the Rio Grande,
roughly halfway between 6R6 and DRT. This line has been
propagating slowly toward the east but northern portions of the
line have been quicker to translate east compared to southern
portions. MRMS-derived hourly rainfall briefly exceeded 2 inches
along the Rio Grande in Val Verde County within the past hour due
to training as the NNE to SSW line orientation aligns with the
mean steering flow.

Large scale ascent ahead of an upper trough axis tracking across
AZ/NM and northwestern Mexico will continue over central TX
overnight and 500-1500 J/kg MLCAPE is forecast to remain in place
(higher values to the south) which should help to fuel intense
cores of heavy rain. A strengthening low level jet with speeds of
30-40 kt, oriented parallel to the Rio Grande, will act to
transport moisture into the ongoing complex with the slowest
movement of the convective line likely to remain near the Rio
Grande, though brief hangups farther north will continue to remain
possible, supportive of SSW to NNE training. The moisture rich
environment with PWs of 1.5 to 1.7 inches and increasingly
divergent/diffluent flow ahead of the upper trough will aid lift
and allow hourly rainfall of 1 to 2 inches, but locally exceeding
2 or perhaps 3 inches at times. While the best potential for the
highest rain rates will remain toward the south, these higher
rates may overlap with portions of the Edwards Plateau which
contain greater sensitivity to flash flooding.

Otto

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!8TCPlAIuJOCoKdzncLt3D4dOp7-uC7Z02-DnORb5M7WF4hNu72dCxZYm4zIwjG3KZecP= Ar1IoDWt7NLkNFlA8tY8-OM$ for graphic product...

ATTN...WFO...EWX...SJT...

ATTN...RFC...FWR...NWC...

LAT...LON 31779963 31379895 30349869 29649894 28929998=20
28780081 29060090 29510140 29640177 30060169=20
31190070=20

=3D =3D =3D
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AWUS01 KWNH 120421
FFGMPD
TXZ000-OKZ000-120920-

Mesoscale Precipitation Discussion 0094
NWS Weather Prediction Center College Park MD
1220 AM EDT Sun Apr 12 2026

Areas affected...north-central TX into south-central OK

Concerning...Heavy rainfall...Flash flooding possible

Valid 120419Z - 120920Z

SUMMARY...Widely scattered to scattered instances of flash
flooding will be possible from north-central TX into south-central
OK through 09Z. Hourly rainfall of 1-2 inches (locally higher)
will be possible with 2 to 4 inches in 2-3 hours.

DISCUSSION...04Z radar imagery showed the northern portion of a
convective line moving into the Edwards Plateau was getting
slightly better organized over the past hour as it moved eastward
across I-20. Instability was on the weak side with 500-1000 J/kg
MLCAPE estimated via SPC mesoanalysis data and the 00Z FWD
sounding, along with PWs near 1.5 inches near and south of the Red
River. Water vapor imagery showed a couple of weaker vorticity
maxima over western TX, ahead of the main upper level shortwave
trough axis across northwestern Mexico which will continue to
provide ascent into the weakly unstable airmass downstream across
central TX into OK tonight.

RAP forecast guidance showed favorably diffluent flow aloft
maintaining over central TX into southern OK through 12Z Sunday.
Expectations are for the current axis of thunderstorms to continue
slowly advancing NNE and E ahead of the upper forcing to the west,
with transient axes of training helping to support 1 to 2+ in/hr
rain rates and possible flash flooding. While the main concern for
higher rates will be with the leading edge of the convective line,
there will be some potential for locally higher rates/training to
refocus to the west of the line as it shifts downstream due to the
diffluent flow aloft and an upstream impulse advancing
northeastward toward the Trans Pecos region of western TX as seen
on water vapor imagery.

Otto

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!-_-Q2hwEx7KarPBlHVSKjNr9BaEBTzQF2g4CKp3yUTtW7BuT45-6zIl9IGBqLsyjXz7B= olzEoDsYjDrWAyUfbyocJiQ$ for graphic product...

ATTN...WFO...FWD...LUB...OUN...SJT...TSA...

ATTN...RFC...FWR...TUA...NWC...

LAT...LON 35979748 35879671 35639634 35089609 34309618=20
33629639 32879660 31959737 31309902 31389998=20
32180015 33440001 34719940 35699834=20

=3D =3D =3D
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AWUS01 KWNH 120831
FFGMPD
TXZ000-121330-

Mesoscale Precipitation Discussion 0095
NWS Weather Prediction Center College Park MD
429 AM EDT Sun Apr 12 2026

Areas affected...Middle Rio Grande Valley into central TX

Concerning...Heavy rainfall...Flash flooding possible

Valid 120828Z - 121330Z

SUMMARY...While the threat is not certain, the potential for at
least localized flash flooding will continue across the middle Rio
Grande Valley into portions of central TX this morning. The
possibility of peak hourly rainfall of 1 to 3 inches will linger
through 13Z.

DISCUSSION...08Z radar imagery showed a weakening squall line over
central TX, moving east toward I-35, north of Austin, where a
relative lull in instability was estimated over central TX via 08Z
SPC mesoanalysis data (peaking near 500 J/kg MLCAPE) while
500-1500 J/kg MLCAPE remained west of I-35 and south of I-10
within the middle Rio Grande Valley. The orientation of the
remnant squall line or outflow boundary was from NE to SW across
the Edwards Plateau to the Rio Grande near Del Rio, generally
aligned with the mean steering flow, resulting in less forward
motion for the southern portion of the outflow boundary. Isolated
convective activity was observed north of the outflow boundary and
south of the Rio Grande over northern Coahuila's Serranias del
Burro.

VAD wind plots showed that 35-40 kt of 850 mb southerly inflow
remained over the lower Rio Grande Valley into the Edwards Plateau
and atop the rain-cooled outflow boundary. Meanwhile, water vapor
imagery showed an approaching lead shortwave trough over the Big
Bend Country, advancing northeastward. Lift ahead of this feature
was evidenced by the recent shower/thunderstorm development over
northern Coahuila. It seems plausible that additional development
may occur along the southwestern flank of outflow, tied to the
eastward translating MCS over central TX with mean steering flow
supporting training from SW to NE, within the lingering
instability max. Aloft, a 90-110 kt upper level jet streak is
forecast to cross the Rio Grande and advance into western OK
through the morning hours, placing favorable right-entrance region
ascent over the Edwards Plateau. In addition, RAP forecasts showed
largely uninhibited MLCAPE returning northward back across eastern
portions of the Edwards Plateau and the I-35 corridor this morning
due to continued low level moisture transport. Therefore, while
coverage of additional thunderstorms remains unclear, at least a
localized flash flood threat will continue over the middle Rio
Grande Valley into portions of central TX through at least 13Z.

Otto

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!_3FlNpW6BRCKRKImp4hH3qvBATr_8e3WL0zq0GV47pVlRjal9jyjHcjYCG8Ay8XtKy5l= 5F2VyGGL6b2WxpXiEWjjrEo$ for graphic product...

ATTN...WFO...EWX...FWD...HGX...SJT...

ATTN...RFC...FWR...NWC...

LAT...LON 31999652 31529594 30669610 30109658 29399760=20
28769895 28629991 28650054 28770069 29250104=20
29710163 30460033 31119904 31969747=20

=3D =3D =3D
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AWUS01 KWNH 121619
FFGMPD
TXZ000-122217-

Mesoscale Precipitation Discussion 0096
NWS Weather Prediction Center College Park MD
1218 PM EDT Sun Apr 12 2026

Areas affected...South-Central Texas

Concerning...Heavy rainfall...Flash flooding possible

Valid 121617Z - 122217Z

Summary...Increasing potential for flash flooding this afternoon
as thunderstorms containing 2-3"/hr rainfall rates develop in the
next 2-3 hours and congeal into an MCS. Locally significant flash
flooding is possible, especially atop sensitive urban areas in the
region.

Discussion...Showers and thunderstorms are showing increased
development across South-Central Texas late this morning as a very
moist airmass continues to destabilize. An intense, localized
cluster of thunderstorms near Gonzales county recently exhibited
2.5-3"/hr rainfall rates according to MRMS and KEWX. When combined
with slow forward motions around 20 kts, a corridor of FFG
exceedance was noted over the last 15 minutes.=20

These early storms are tapping into a very favorable environment
for efficient heavy rainfall production; 12Z RAOB from BRO and
ACARS profiles from AUS and SAT depict a deep moist layer from the
surface to 750 mb (PWAT of 1.7-1.8"), tall instability profiles
characterized by 1000-2000 J/kg of MUCAPE, and WBZ heights over
3500 m. An inversion above the moist layer has thus far suppressed
more widespread development, although this is expected to weaken
over time as large scale ascent strengthens over the next few
hours while the column continues to moisten.

As such, thunderstorms are expected to expand in coverage and
intensity over the next few hours. By 17-18z, the 12z CAM suite is
in good agreement for this activity to congeal into an MCS
containing training thunderstorms along a NE-SW axis -- possibly
along a remnant cold pool evident in surface obs. Forecast Corfidi
vectors near 10 kts suggest this complex will be quite slow to
move once it develops, in turn lengthening the residence time of
2-3"/hr rainfall rates within the strongest individual cells.
While the area has been dry according to NASA SPoRT soil moisture
percentiles, the risk of flash flooding is expected to increase
over the next 6 hours as 3-6" fall in the main axis of training.
Significant flash flooding is possible should this fall over a
sensitive urban area.

Asherman

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!6l5fxvgg0Ga24XrcAiL7fdIFH_5gslDM_qZveZxQ_cc0YwW17qlWHwCr4bDlkiesKVsA= EMVZR837bFWVyXMVWomDxKs$ for graphic product...

ATTN...WFO...EWX...FWD...HGX...

ATTN...RFC...FWR...NWC...

LAT...LON 31379590 30859516 29989564 29049725 28959831=20
29579882 30369847 31079733=20

=3D =3D =3D
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AWUS01 KWNH 122018
FFGMPD
TXZ000-130216-

Mesoscale Precipitation Discussion 0097
NWS Weather Prediction Center College Park MD
417 PM EDT Sun Apr 12 2026

Areas affected...portions of central TX

Concerning...Heavy rainfall...Flash flooding possible

Valid 122016Z - 130216Z

Summary...Showers and thunderstorms are developing across portions
of central TX. Hourly rain amounts to 3" with local totals to 5"
are possible, which could lead to scattered instances of flash
flooding over partially saturated soils.

Discussion...The combination of shortwaves aloft crossing the
TX/OK border and northern Mexico have led to a difluent pattern
aloft across the region. Precipitable water values are 1.5-1.8"
per GPS data. Effective bulk shear of ~50 kts exists. ML CAPE is
around 2000 J/kg (higher to the west and lower to the east).

Inflow at 850 hPa slowly backs with time as the upper level
shortwave in northern MX approaches, which along with no
additional eastward progress in the instability gradient should
hold up forward forward propagation to the northeast. The 12z
GFS-based Galvez-Davison index implies that the current convective
uptick maximizes in the 21-00z period before slowly fading
thereafter in this area. Both the 12z HREF and 12z REFS have a
heavy rainfall signal across the region, though of differing
magnitudes. Given the above ingredients which favor mesocyclone
formation and cell training, along with the possibility that
storms of different levels of organization could merge, hourly
amounts to 3" with local totals to 5" are possible. Given the
recently compromised flash flood guidance values due to recent
heavy rainfall, scattered instances of flash flooding are
possible.

Roth

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!8j2UxM1SGtHNsq_QI1ob82WzX2FdtDrZMFk4nPqkt6h33-miTPan9qw8F2P0QPMkg4eY= Z1hEz4csPMkB4OnF9cs_Ej8$ for graphic product...

ATTN...WFO...EWX...FWD...SJT...

ATTN...RFC...FWR...NWC...

LAT...LON 32359813 32339732 31189682 29479732 29309826=20
30019894 31669899=20

=3D =3D =3D
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AWUS01 KWNH 122101
FFGMPD
TXZ000-130259-

Mesoscale Precipitation Discussion 0098
NWS Weather Prediction Center College Park MD
500 PM EDT Sun Apr 12 2026

Areas affected...portions of southeast TX

Concerning...Heavy rainfall...Flash flooding possible

Valid 122059Z - 130259Z

Summary...Thunderstorms with some level of organization will
continue to attempt to train into this evening. Hourly amounts to
3" with additional local totals to 5" are possible, which could
lead to scattered instances of flash flooding.

Discussion...Thunderstorms with heavy rainfall have been moving
east-northeast inland of the Middle & Upper TX Coasts near the
tail end of an MCV moving through portions of MO, which shows up
as an eastward branch of the 850 hPa inflow/convergence. Earlier
this afternoon, hourly rain amounts were quite high, though
they've settled back towards 2.5-3" as of late. Precipitable
water values are 1.8-2" per GPS data. ML CAPE is 1000-1500 J/kg.=20
Effective bulk shear is 25-35 kts which is organizing convection.

Both the 12z REFS and 18z HREF are at least a county too far
inland with this convective activity. While their six hour
probabilities show a tendency for the activity to approach the
TX/LA border, the REFS hourly probabilities in particular are
fairly far to the east/too quick when compared to recent radar
reflectivity imagery. A combination of cell training and embedded
mesocyclones appear to be the main cause for heavy rainfall in
this region, though merging convection cannot be ruled out could
any cells form south of the band and approach it. ML CAPE
supports the idea of this activity making a run for the LA border,
but with decreasing instability with time, there could be a
tendency for increased forward propagation/decreased precipitation
amounts with time. With somewhat higher instability to the north
the farther east you go in this region, thunderstorm activity may
try to correct towards the 18z HREF solution and edge a little
more northward as well. Hourly rain amounts to 3" with additional
local totals to 5" remain possible, which could lead to scattered
instances of flash flooding.

Roth

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!5nMBgV5t9cCt79LlQETJWpm7K6GjQ240BRaV-E-svg4sWr9O9XPQSrTHrurNmmfxbRjA= aPMRiPqOIy0SlzDTLr2vtxk$ for graphic product...

ATTN...WFO...HGX...LCH...SHV...

ATTN...RFC...FWR...NWC...

LAT...LON 31319378 30159385 29649511 29629620 29979635=20 =20=20=20=20=20=20=20=20=20=20=20=20

=3D =3D =3D
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AWUS01 KWNH 130324
FFGMPD
TXZ000-130700-

Mesoscale Precipitation Discussion 0099
NWS Weather Prediction Center College Park MD
1123 PM EDT Sun Apr 12 2026

Areas affected...central TX

Concerning...Heavy rainfall...Flash flooding likely

Valid 130322Z - 130700Z

Summary...A small, slow moving cluster of thunderstorms is
expected to maintain peak rainfall rates of 2 to 3+ in/hr and
localized flash flooding across portions of central TX over the
next 2-4 hours. Afterward, eastward translation and weakening is
anticipated.

Discussion...03Z radar imagery showed a small thunderstorm cluster
over and just west of the Colorado River in San Saba and Llano
counties. This cluster has had a history of backbuilding and
training with observed hourly rainfall of 2.5 inches and
MRMS-derived estimates locally over 3 inches over San Saba County.
It was located just on the cool side of an elongated, remnant
outflow boundary from earlier on Sunday that extended from near
New Braunfels into the Hill Country and northward across I-20,
just east of Abilene. Water vapor imagery showed a number of
vorticity maxima embedded within the WSW flow aloft. At 03Z, a
more notable vorticity max was located just northeast of San
Antonio, with another more subtle feature over Concho and Menard
counties, west of the ongoing thunderstorms.

Expectations are for low level flow overrunning the outflow to
continue to support thunderstorms over portions of central TX
within a moderately unstable airmass characterized by 1500 to
2000+ J/kg MLCAPE and PWs of 1.5 to 1.7 inches (SPC mesoanalysis).
However, passage of the vorticity maxima/shortwave features aloft
should cause the ongoing activity to shift east in another couple
of hours while additional development occurs downstream toward the
east, with eventual weakening as increasing CIN is encountered
toward the east. There is some uncertainty with exactly how long
the backbuilding signature will continue over San Saba and Llano
counties, but current thinking is that the passage of the embedded
impulses aloft should disrupt the ongoing activity within the next
2-3 hours.

Otto

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!8pcpmXpFhE2czLV347fybNztipkC3atoiLr2jFxkU4IQKY_67vA06heOHYA0UdhIf3n0= ErkfDhUi8YwEmk5Z5Ni57eA$ for graphic product...

ATTN...WFO...EWX...FWD...SJT...

ATTN...RFC...FWR...NWC...

LAT...LON 32069713 31929682 31659668 31359660 31129663=20
30859695 30689738 30599828 30679895 30929919=20
31089929 31379914 31579875 31879812 32039757=20 =20=20=20=20=20=20=20=20=20=20=20=20

=3D =3D =3D
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AWUS01 KWNH 132142
FFGMPD
MIZ000-WIZ000-MNZ000-IAZ000-140330-

Mesoscale Precipitation Discussion 0100
NWS Weather Prediction Center College Park MD
541 PM EDT Mon Apr 13 2026

Areas affected...Much of Wisconsin, Southeastern Minnesota, and
U.P. of Michigan

Concerning...Heavy rainfall...Flash flooding likely

Valid 132140Z - 140330Z

SUMMARY...Thunderstorms forming along a warm frontal boundary will
organize into training lines of storms, over an area of saturated
soils through this evening. Flash flooding likely.

DISCUSSION... Several areas of convection have begun to form along
a warm frontal boundary across much of Wisconsin and southeast
Minnesota this afternoon. These storms are being fed by moisture
influx with PWATs around 1 inch along the front, but over 1.3
inches along the Illinois/Wisconsin border, based on the latest
SPC Mesoanalysis. CAMs guidance is in good agreement that the
storms will continue to grow upscale into an MCS that will then
support training storms propagating eastward across central and
northern Wisconsin. A cold front shown across northern Minnesota
will press southeastward and eventually help to push the MCS
southward with time.

Soils across Minnesota and Wisconsin are nearly saturated due to
recent rainfall and around the U.P. of Michigan, recent snowmelt
as shown on NASA SPoRT imagery. With above average river levels
and nearly saturated soils across nearly all of Wisconsin, almost
all of the rainfall expected from this forecast MCS will convert
to runoff quickly. FFGs across this region on average are around
1.5 inches/1 hour, 2 inches/3 hours, and 2.5 inches/6 hours. These
values are likely to be exceeded with multiple rounds of training
storms expected late this afternoon and this evening. The cells
south of the Twin Cities have a history of rainfall rates
exceeding 2 inches/hour at times, showing that the atmosphere is
capable of rates exceeding these aforementioned FFG values.

Wegman

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!7G1XSLTDBBKEgE6KnC6HjiSFk-T-6U4Bgr0ABoBXm8-JrDZHBYlj134353NlsdE9nf1H= lWiBku11TKmoojCTL9tJ1SM$ for graphic product...

ATTN...WFO...ARX...DLH...GRB...MKX...MPX...MQT...

ATTN...RFC...MSR...NWC...

LAT...LON 46828894 46588739 45458680 44468747 43548763=20
43368904 43429003 43509140 43739228 44039312=20
44719364 45179376 45829361 46349312 46619141=20 =20=20=20=20=20=20=20=20=20=20=20=20

=3D =3D =3D
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AWUS01 KWNH 132331
FFGMPD
MNZ000-IAZ000-SDZ000-140330-

Mesoscale Precipitation Discussion 0101
NWS Weather Prediction Center College Park MD
730 PM EDT Mon Apr 13 2026

Areas affected...Southwest Minnesota and Northwest Iowa

Concerning...Heavy rainfall...Flash flooding possible

Valid 132330Z - 140330Z

SUMMARY... Clusters of storms are forming across portions of
southwest Minnesota and northwest Iowa this evening. Localized
rain rates to 2" per hour could cause isolated to widely scattered
instances of flash flooding.

DISCUSSION... Convective coverage has rapidly increased across
portions of southwest Minnesota and northwest Iowa this evening as
part of a broader low pressure center and warm frontal system,
tapping into Gulf moisture riding up to the south and east of
these features. Rainfall rates of up to 2 inches per hour have
been observed on radar, with somewhat moistened soils in the area
from recent rainfall, based on NASA SPoRT imagery.

CAMs guidance is in poor agreement in this area, with none of the
guidance suggesting convective coverage would be as robust in this
area than has already formed. For those that have a hint of the
southern extent of this convection (NAMnest, ARW to a lesser
extent, and HRRR to an even lesser extent), all suggest much
faster and more eastward motions to these storms than have already
been occurring. Thus, with slower and more northward storm
motions, towards areas where storms have already formed across far
southern Minnesota, expect more robust training and heavier
rainfall rates than the guidance is suggesting, favoring more
potential for flash flooding over the next few hours.

Wegman

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!6X1tqeZU-LUfkuQOxQe1ZCk91388CwJGlSqrn-Xsd_p7IlWiLuBHXrVEhhbbR6vhNbAj= BNCnIg_odYgJqLuN6203qEk$ for graphic product...

ATTN...WFO...ARX...DMX...FSD...MPX...

ATTN...RFC...KRF...MSR...NWC...

LAT...LON 45369378 44999377 44649360 44179331 43929301=20
43769257 43649215 43449216 43129229 42679296=20
42619447 42549518 42579577 42809622 43209651=20
43539693 44139664 44909551 45309470 45349421=20 =20=20=20=20=20=20=20=20=20=20=20=20

=3D =3D =3D
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AWUS01 KWNH 140347
FFGMPD
MIZ000-WIZ000-IAZ000-140800-

Mesoscale Precipitation Discussion 0102
NWS Weather Prediction Center College Park MD
1145 PM EDT Mon Apr 13 2026

Areas affected...southern WI into central/northern Lower MI

Concerning...Heavy rainfall...Flash flooding likely

Valid 140344Z - 140800Z

Summary...Areas of flash flooding will be likely from southern WI
into central/northern Lower MI over the next 4-5 hours. Saturated
to nearly saturated soils are expected to be a contributing factor
to excess runoff from rainfall rates of 1-2 in/hr.

Discussion...0320Z radar imagery across the Upper Midwest showed
an MCS with an elongated convective line on its southern flank,
oriented west-east from the MN/WI/IA tri-state region into
northwestern Lower MI. The cluster of thunderstorms were located
along a quasi-stationary front that extended west to east through
central WI/MI with 500-2000 J/kg MLCAPE (highest over northeastern
IA, lowest over Lower MI) estimated just south of the boundary per
03Z SPC mesoanalysis data. Infrared imagery showed cloud tops
continued to cool with divergence aloft aided within the
right-entrance region of a 110-130 kt upper level jet streak
positioned over Lake Superior into southern Quebec. 850 mb VAD
wind data showed 50-60 kt of SSW flow from eastern IA into
northern IL and southern WI, aiding rapid moisture transport
across Lake Michigan into Lower MI with upstream moisture over the
Midwest between 1.2 and 1.4 inches.

As the main surface low along the front in northwestern IA
advances ENE tonight, continued southerly flow ahead of the low
into the ongoing complex of storms should sustain convection
within the unstable airmass for several more hours. Mean cell
motions from the W to SW will interact with the southerly low
level inflow allowing for segments of the line to advance
southeastward at times. Cell mergers and training within the
linear segments of the MCS will attain rainfall rates of 1-2 in/hr
at times with an overall movement toward the east through 08Z.
Most soils across the region are saturated due to snowmelt and/or
recent rainfall, with additional heavy rainfall more quickly
translating into runoff compared to average. Therefore, areas of
flash flooding are likely to occur across southern WI into Lower
MI over the next 4-5 hours.

Otto

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!7L1O-mnGFqvdnGQKawceVca5wKPKEE_53aZyZ3QByeXtRcHpH_iNlJdj0PPvcB--9qxe= 996tFkVy9okNckkMMmvxAfw$ for graphic product...

ATTN...WFO...APX...ARX...DTX...GRB...GRR...MKX...

ATTN...RFC...MSR...NWC...

LAT...LON 45818459 45288327 44528305 43748367 42798585=20
42498773 42528950 42719070 43409120 44019101=20
44319034 44578902 45028737 45468637=20

=3D =3D =3D
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AWUS01 KWNH 141802
FFGMPD
INZ000-WIZ000-ILZ000-MNZ000-IAZ000-150000-

Mesoscale Precipitation Discussion 0103
NWS Weather Prediction Center College Park MD
200 PM EDT Tue Apr 14 2026

Areas affected...Eastern IA...Southern WI...Northern and Eastern
IL...Western and Central IN

Concerning...Heavy rainfall...Flash flooding possible

Valid 141800Z - 150000Z

SUMMARY...Developing and expanding clusters of heavy showers and
thunderstorms coupled with locally wet/sensitive antecedent
conditions will foster an isolated to scattered threat for flash
flooding going through early this evening.

DISCUSSION...Early afternoon GOES-E visible satellite imagery
shows stronger diurnal heating promoting a steady destabilization
of the boundary layer across eastern IA, western IL and nosing
into southwest WI. This airmass is pooling south and east of a
quasi-stationary front as multiple waves of low pressure advance
along it.

Some modest CINH remains in place across these areas, but MLCAPE
values of 2000 to 3000 J/kg are already in place, and this is
being supported by steep mid-level lapse rates transiting the
Midwest. Meanwhile, satellite imagery shows a modest mid-level
shortwave impulse ejecting northeastward across central and
eastern IA down through northern MO and into western IL. This
energy coupled with additional solar insolation should erode the
remaining CAP across the region and set the stage for convective
initiation. Much of this should be focused in close proximity to a leftover/diffuse outflow boundary from the early-day convection.

As convection grows upscale, there will gradually be concerns for
a few cell-mergers and some cell-training. A combination of
multicells and supercells will be likely given the strong
instability in conjunction with strong shear (effective bulk shear
approaching 50 kts). The larger scale environment is also
increasingly moist with aid from a southwest low-level jet of 30
to 40+ kts. Deeper layer southwesterly moisture transport is noted
aloft too with elevated CIRA-LVT magnitudes.

Locally significant model disagreement is noted through this
evening with the placement of the convection and its general
evolution, but a multi-model consensus suggests eastern IA,
northern IL and southern WI seeing one focus for convection, with
areas of central/eastern IL and into western IN seeing a second
focus.

Rainfall rates will be capable of reaching 1 to 2 inches/hour,
with some localized totals by early this evening of 2 to 4 inches.
The antecedent conditions are locally quite sensitive, and
especially from eastern IA through northern IL and southern WI.
Isolated to scattered areas of flash flooding will be possible as
a result.

Orrison

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!6rVoRhS9MtZ95Sj6aCH05vO57EMIhqP-DU7yZfIuOyX3spDEUeEb69FAjBiqp3DRaLHv= v5fBXogv1SsUKymmwi2Cj7Y$ for graphic product...

ATTN...WFO...ARX...DMX...DVN...ILX...IND...IWX...LOT...MKX...

ATTN...RFC...MSR...TIR...NWC...

LAT...LON 43969015 43808891 43378810 42458766 41648679=20
41038574 40368523 39538567 39238682 39538845=20
40048943 41199043 41619249 41909331 42369330=20
42689297 43329238 43909121=20

=3D =3D =3D
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AWUS01 KWNH 142204
FFGMPD
TXZ000-OKZ000-150402-

Mesoscale Precipitation Discussion 0104
NWS Weather Prediction Center College Park MD
603 PM EDT Tue Apr 14 2026

Areas affected...portions of western North Texas and the
southeastern Texas Plains into southern and central Oklahoma

Concerning...Heavy rainfall...Flash flooding possible

Valid 142202Z - 150402Z

Summary...Ongoing convective evolution suggests an increasing
flash flood threat for areas near Vernon, Lawton, and eventually
toward the I-35 corridor in central Oklahoma through 04Z/11p
Central.

Discussion...Scattered, deep convection continues to increase in
coverage across western north Texas and southwestern Oklahoma.=20
Recent surface obs indicate subtle veering of flow west of a
dryline across the Texas South Plains, and objective
analyses/satellite suggest subtle vort maxima riding atop the
dryline and over a warm, unstable airmass over the discussion
area. These trends suggest continued expansion of convective
coverage across the discussion area over the next few hours
(especially as the low-level jet ramps up), with areas of training
and mergers expected to foster spots of 1-2.5 inch/hr rain rates
especially near the Red River.

Antecedent conditions are a somewhat moist across the region from
prior heavy-rain events over the past week. Sensitive terrain and
urbanized areas (near Lawton in particular) could also experience
a higher runoff risk. The overall focus for flash flooding should
revolve around sensitive spots and locations of cell mergers -
with background/mean flow fields (around 35-45 knots) suggestive
that prolonged heavier rainfall (and >1.5 inch/hr rates/local FFG)
may not occur on a widespread basis.

Flash flooding is possible with this regime initially over
southwestern OK and western north Texas, with the risk spreading
northeastward toward I-35 in Oklahoma later tonight.

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!6VoGB_M1a_9ytYeE6UWe8iLQ051eCBJO1BKLKOA725_8XkZLNT0flAJJgr3NBTOQttOi= 3Q_C8zlaihqgqTHhLhv-AsE$ for graphic product...

ATTN...WFO...AMA...FWD...LUB...OUN...SJT...TSA...

ATTN...RFC...FWR...TUA...NWC...

LAT...LON 35969737 35969640 34589601 33539662 33169844=20
32870002 32960060 33570089 34530062 35180008=20
35599891=20

=3D =3D =3D
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AWUS01 KWNH 142357
FFGMPD
MIZ000-WIZ000-ILZ000-150556-

Mesoscale Precipitation Discussion 0105
NWS Weather Prediction Center College Park MD
756 PM EDT Tue Apr 14 2026

Areas affected...portions of Wisconsin and Michigan

Concerning...Heavy rainfall...Flash flooding likely

Valid 142356Z - 150556Z

Summary...Deep convection will continue to produce heavy rainfall
while migrating eastward through Wisconsin, across Lake Michigan,
and eventually into Lower Michigan. Flash flooding is likely
given ongoing impacts and local sensitivities in the region.

Discussion...Deep convection has evolved as expected from the
Mississippi River eastward across much of Wisconsin and
northeastern Iowa. Favorable interactions with a warm frontal
zone and steep lapse rates aloft have enabled intense updrafts and
embedded mesocyclones to occasionally merge and produce spots of 2
inches/hr of rainfall at times. Areas of flash flooding are
possible in the short term.

Of particular concern is the potential for storms to expand
northeastward and eastward in coverage. The position of warm
frontal zone over central Wisconsin and cooler Lake Michigan
waters may weaken convection as storms move atop slightly
cooler/stable low-level air, although very steep lapse rates aloft
downstream should maintain convection as it migrates toward areas
that have experienced 3-5 inches of rainfall over the past 3 days,
with ongoing impacts to local watersheds in the area. FFGs fall
to below 1 inch/hr in a few downstream areas, highlighting the
sensitivity of the ground conditions there. Approaching heavy
rainfall may worsen ongoing recovery efforts and perhaps cause new
instances of flash flooding to occur.

Peak flash flood potential will spread into northeastern Wisconsin
in the 00-04Z timeframe and eventually spread into Lower Michigan
generally from 02Z onward.

Cook

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!7kgjJfhxvhUeO4YT74P3s8DQ6l_xpQ24IGlUfxoboD8Y2QG0QSY5486_Dp46h_RYXL9-= Huhx9HqLAuI5qFzRolT1pZE$ for graphic product...

ATTN...WFO...APX...ARX...DTX...DVN...GRB...GRR...IWX...LOT...
MKX...MQT...

ATTN...RFC...MSR...TIR...NWC...

LAT...LON 45408569 45298379 44028325 42218366 41788510=20
41898733 42518836 42508976 43319091 44929033=20
45348892=20

=3D =3D =3D
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AWUS01 KWNH 150024
FFGMPD
INZ000-WIZ000-ILZ000-IAZ000-150623-

Mesoscale Precipitation Discussion 0106
NWS Weather Prediction Center College Park MD
824 PM EDT Tue Apr 14 2026

Areas affected...eastern Iowa, northern Illinois, southern
Wisconsin

Concerning...Heavy rainfall...Flash flooding likely

Valid 150023Z - 150623Z

Summary...Thunderstorms are expected to not only persist, but
train and repeat over areas very near the WI/IL border vicinity
over the next several hours. Flash flooding is likely, and
significant impacts cannot be ruled out.

Discussion...Radar mosaic imagery depicts a mature convective
complex with embedded linear structures and mesocyclones extending
from south-central WI (near Madison) southwestward to near Dubuque
and Cedar Rapids. Other convection was anchored/backbuilding near
a warm front close to and just north of Milwaukee. Each of these
convective clusters were producing expanding cold pools that were
progressively orienting perpendicular to increasing southwesterly
low-level flow, with 45kts now noted on mesoanalyses at 850mb
across much of IA/IL. Latest indications are that these
convective clusters will continue to backbuild and train owing to
convergence along strengthening outflows and strong upstream
buoyancy (~3000 J/kg MLCAPE).=20

The scenario is beginning to favor multiple hours of repeating
convection (1-2.5 inch/hr rain rates) very close to where ongoing
convection exists currently. Localized 3-5 inch rainfall totals
are possible over the next 6 hours. This could result in
significant flash flood potential as FFG thresholds across the
area are only at around 1 inch/hr and will be readily exceeded.=20
This potential will likely exist through 06Z/1a central, with
populated areas near Madison, Milwaukee, Rockford, and perhaps
Chicago potentially experiencing impacts.

Cook

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!_RimPN4452Lz3CSs_IelT7ml5jPYxQHeJmRoaCJABg12dpxpwKNOMVjDMdImE2PL8K-g= NjzLo2BW4jUzEE5JhCUattE$ for graphic product...

ATTN...WFO...ARX...DMX...DVN...LOT...MKX...

ATTN...RFC...MSR...NWC...

LAT...LON 43498958 43368824 42998765 41958741 41538758=20
41248859 41319028 41369158 41559227 41839253=20
42249259 43009239 43179125=20

=3D =3D =3D
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AWUS01 KWNH 150528
FFGMPD
OHZ000-MIZ000-INZ000-WIZ000-ILZ000-151020-

Mesoscale Precipitation Discussion 0107
NWS Weather Prediction Center College Park MD
127 AM EDT Wed Apr 15 2026

Areas affected...northeastern IL/southeastern WI to southern
MI/northern IN

Concerning...Heavy rainfall...Flash flooding possible

Valid 150526Z - 151020Z

SUMMARY...Scattered flash flooding will be possible in the
vicinity of the eastern IL/WI border, eastward to southern Lower
MI, northern IN and northwestern OH. Rainfall rates of 1-2 in/hr
(locally higher) are expected along with peak additional rainfall
totals of 2-3 inches through 10Z

DISCUSSION...05Z radar imagery depicted a trailing stratiform MCS
moving across Lower MI with the leading edge pressing
southeastward across southern MI into northern IN. An outflow
boundary was analyzed ahead of the convective line from
southeastern MI into northern IN/IL with upstream thunderstorm
development occurring north of the western portion of the boundary
along the WI/IL border. 925-850 mb winds were from the SW at 45-55
kt to the south of the boundary over north-central IL and
1000-2000 J/kg MLCAPE extended from the MI/IN border back west to
the MS River, per SPC mesoanalysis data.

The leading edge of the MCS is expected to continue tracking
toward the ESE across southeastern MI into northern IN and
northwestern OH over the next 1 to 2 hours, but back to the west,
continued convective development is likely as moist, low level
flow overruns the slow moving western portion of the rain-cooled
outflow. Mean cell motions are generally from the west which will
setup a favorable pattern for training from west to east given
alignment with the low level boundary. Rainfall rates of 1 to 2
in/hr are likely (locally higher possible), and an additional 2 to
3 inches of rain is expected through 10Z where cell training is
maximized. Flash flood guidance is less than 2 inches in 3 hours
for some locations, especially across northern IL/southern WI
where heavy rain over the past 12-24 hours has contributed to
reduced soil infiltration.

Otto

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!4gUZnv0Qxp7R8HWlZNMdEUOjnXzvwcsKhaQiAxAI-iAuF1r4A3I0uJ-ZiXaLC7iOJvba= 8vQFf0NVtX6daqnhMsw5PxE$ for graphic product...

ATTN...WFO...CLE...DTX...GRR...IWX...LOT...MKX...

ATTN...RFC...MSR...TIR...NWC...

LAT...LON 43668276 43568226 43138209 42448225 41578312=20
41298455 41268640 41468819 41788922 42428939=20
42908878 42848652 42988484 43578350=20

=3D =3D =3D
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AWUS01 KWNH 152148
FFGMPD
WIZ000-ILZ000-IAZ000-160246-

Mesoscale Precipitation Discussion 0108
NWS Weather Prediction Center College Park MD
547 PM EDT Wed Apr 15 2026

Areas affected...southern Wisconsin, northern Illinois

Concerning...Heavy rainfall...Flash flooding likely

Valid 152146Z - 160246Z

Summary...Thunderstorms will migrate eastward across wet/sensitive
areas from yesterday's rainfall especially across Wisconsin.=20
Flash flooding is likely.

Discussion...Scattered thunderstorms have organized along a
frontal boundary from just north of Dubuque to Des Moines. The
storms are exhibiting linear organization so far in their
evolution, with forward propagation and 40-50 kt speeds generally
limiting their rainfall potential to around 1 inch/hr or less.=20
Flash flooding is possible on an isolated basis in the short term.

Over the next 1-4 hours, however, storms will migrate eastward
along a remnant outflow/frontal boundary extending east-west
across southern Wisconsin (generally from Sheboygan to Wisconsin
Dells). As low-level flow increases over Illinois, convergence
along this boundary could result in additional convection
developing in southern/southeastern Wisconsin out ahead of the
ongoing quasi-linear complex. This will increase potential for training/mergers and prolonged rainfall rates in areas that have
already experienced 1-4 inches of rainfall yesterday near/north
and west of Milwaukee and across far northern Illinois. FFGs are
less than 1 inch/hr in some spots and could readily be exceeded
where mergers take place. Flash flooding is likely - especially
in sensitive areas that received rainfall/runoff issues late
yesterday and early today.

Cook

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!5opxEbcOifoi00puOb7C5zg01c-pm_jWC9NSJEfq1mEfdNRUZ1jcte1ysb-WmCRTq14u= t29w5aSU3WiQJFXPtvtydIo$ for graphic product...

ATTN...WFO...ARX...DVN...GRB...LOT...MKX...

ATTN...RFC...MSR...NWC...

LAT...LON 44558947 44408783 43208786 42008773 41548866=20
41449051 42319153 43979095=20

=3D =3D =3D
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AWUS01 KWNH 152301
FFGMPD
ILZ000-MOZ000-OKZ000-KSZ000-160459-

Mesoscale Precipitation Discussion 0109
NWS Weather Prediction Center College Park MD
700 PM EDT Wed Apr 15 2026

Areas affected...much of Missouri, a small part of southeastern
Kansas

Concerning...Heavy rainfall...Flash flooding possible

Valid 152259Z - 160459Z

Summary...Deep convection is organizing into clusters/segments
with localized training. Localized flash flooding is possible
especially in low-spots and sensitive areas.

Discussion...Convection continues to mature along and east of a
dryline extending from near Kansas City south-southwestward to
near Bartlesville and Oklahoma City, Oklahoma. The storms are in
a very moist, unstable airmass (with 2000 J/kg SBCAPE and 1.5 inch
PW values) supporting locally heavy rainfall at times despite
appreciable storm motions of around 30-40 knots.

The storms are in an environment with modest forcing for ascent
due to the slow movement of the dryline, with an approaching
vort-max over Nebraska and confluence ahead of the dryline helping
to deepen and expand convective coverage. Because storms aren't
strictly confined to the dryline, a few areas of training have
been noted (especially across far southwestern Missouri near
Joplin). These trends should continue for several more hours as
evidence of any distinct upscale growth into forward-propagating
linear segments (that would effectively reduce rain rates) is
currently unclear.

Localized training/repeating is likely to result in spots of 1-2
inch/hr rain rates at times on a localized basis. These rain
rates will threaten local FFG thresholds, with local sensitivities
also contributing to a potential flash flood risk. This risk will
persist for several hours this evening - perhaps through 03-04Z
tonight.

Cook

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!4QBPUYiOvvcrSPYpuhtkEviwBvLAooHGfmdwrtbeqZBMskhBe_do-t8cvF3LxHUIUCMe= m9tMCSe9Cl1O5RzzcsdF2es$ for graphic product...

ATTN...WFO...DVN...EAX...ICT...LSX...PAH...SGF...TSA...

ATTN...RFC...KRF...MSR...ORN...TUA...NWC...

LAT...LON 40509182 39399086 37999060 37039114 36699282=20
36749448 37119532 38149503 39479452 40199364=20 =20=20=20=20=20=20=20=20=20=20=20=20

=3D =3D =3D
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AWUS01 KWNH 160012
FFGMPD
ARZ000-TXZ000-OKZ000-160609-

Mesoscale Precipitation Discussion 0110
NWS Weather Prediction Center College Park MD
810 PM EDT Wed Apr 15 2026

Areas affected...southern/southeastern Oklahoma, far north Texas,
far western Arkansas

Concerning...Heavy rainfall...Flash flooding possible

Valid 160009Z - 160609Z

Summary...An axis of training convection has materialized from
near Wichita Falls through Ardmore to near McAlister. This heavy
rain axis should translate east-northeastward over the next few
hours, with flash flooding possible especially across southern
Oklahoma.

Discussion...Initial scattered convection has recently aligned
into a focused, training axis of cells along the Red River Valley
this evening. The storms are in a weakly forced environment, with
forcing for ascent resulting from the glancing influence of a
mid-level wave over Nebraska and weakly confluent low-level flow
across the region. The orientation of cells parallel to mean flow
aloft - combined with their gradual maturity and establishment of
cold pools - suggests that training convection will continue to be
an issue for at least a few hours. This training band of
convection will gradually translate east-northeastward into more
of eastern Oklahoma and perhaps far western Arkansas through the
overnight hours. A secondary training band of convection
near/north of the Dallas/Fort Worth metroplex may also materialize
over the next couple hours.

Ground conditions are relatively dry in many areas, with hourly
FFG thresholds exceeding 2-2.5 inches in spots. This suggests
isolated flash flood potential across the region - mainly tied to
low spots and/or urban areas. Persistence of training, however
(as evidenced by 2-2.5 inch/hr rain rates near Ardmore) suggests
that appreciable impacts may occur where rainfall is heaviest and
most persistent. This isolated flash flood threat should persist
for several hours - perhaps through 06Z/1a central.

Cook=20

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!94K4h8YfYfUxaStsHe_mwQL2Cg4STxUAwOgtVe0vJgX8kBrY3h64uUeSF04aU6SgfTz9= sW5g0eOrXgiqZql0yM0HAKo$ for graphic product...

ATTN...WFO...FWD...LZK...OUN...SHV...TSA...

ATTN...RFC...FWR...ORN...TUA...NWC...

LAT...LON 35899509 35869426 34929421 33509505 33079635=20
32859832 34239831 35069740=20

=3D =3D =3D
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AWUS01 KWNH 160234
FFGMPD
MIZ000-INZ000-WIZ000-ILZ000-160800-

Mesoscale Precipitation Discussion 0111
NWS Weather Prediction Center College Park MD
1033 PM EDT Wed Apr 15 2026

Areas affected...Northern IL...Far Southeast WI...Southern L.P. of
MI...Far Northwest IND...

Concerning...Heavy rainfall...Flash flooding likely

Valid 160235Z - 160800Z

SUMMARY...Potential for localized flash flooding continues through
the early overnight period; though coverage should become more
scattered with loss of heating/rainfall intensity. Rates of
1.5-1.75"/hr and spots of 2-3" remain possible.

DISCUSSION...Regional RADAR depicts a mature MCV across central
Lake Michigan just east of Milwaukee progressing toward
Holland/Muskegon, MI with a trailing QLCS convective line
extending across SE WI into the NW Exurbs of Chicago along W I-88
in N IL toward the Quad Cities. The cold pool appears to be
maturing as well, increasing forward propagation of the line
particularly through the middle, toward the WI/IL line, this is
reducing overall residency time for extreme rainfall totals, but
the short-term heavy bursts may still result in 1-1.5" in 30 to 60
minutes. Given recent heavy rainfall and saturated upper soil
profiles and proximity to hydrophobic urban conditions near
Chicago will result in increased run-off and likely incidents of
localized flash flooding/rapid rise flood, especially in the next
few hours.

GOES-WV shows expanding divergence region along the entrance of a
100 kt 3H speed max across the LP of MI at this time, helping to
maintain the MCV crossing the more stable air of Lake Michigan but
solid southwesterly warm-air advection is allowing for downstream
convergence with limited but sufficient MUCAPE of 500-750 J/kg.=20
VWP shows solid 850-700 40-45kt flow at the western nose of the
deep layer moisture axis where overall PW totals are increasing to
over 1.25". This will likely continue to support 1.5-1.75"/hr
rates and given the record wet spring across the SW LP; FFGs are
compromised in spots and while typically sandy and able to absorb
these rates and totals up to 2-3", saturation over 75% to 85% will
still quickly be overwhelmed with above normal run off and
potential for localized flash flooding conditions. However,
proximity to the unstable air will be increasing (along with
overall diurnal loss) and overall intensity of thunderstorms will
be steadily increasing through the night reducing overall coverage
and magnitude of flooding potential.

Gallina

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!4LPc5RRJ7D_EWUR-GQyFYstxacfepZIrau-Gq7EetmrgliaA_S5VAKvEdlNZqw0hlovq= memycrUKXrRQJ4-THjJqulI$ for graphic product...

ATTN...WFO...DTX...DVN...GRR...IWX...LOT...MKX...

ATTN...RFC...MSR...NWC...

LAT...LON 43868583 43758458 43508280 42468379 41648587=20
41268769 41238976 41499024 42108976 42648902=20
42968835 43578710=20

=3D =3D =3D
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AWUS01 KWNH 160311
FFGMPD
ILZ000-MOZ000-160800-

Mesoscale Precipitation Discussion 0112
NWS Weather Prediction Center College Park MD
1110 PM EDT Wed Apr 15 2026

Areas affected...Central Illinois...East-Central/Southeast
Missouri...

Concerning...Heavy rainfall...Flash flooding possible

Valid 160310Z - 160800Z

SUMMARY...Mature MCV continues to provide solid WAA ascent coupled
with nose of enhanced deep layer moisture likely to support
efficient rainfall production with rates of 1.5-1.75" and streaks
of 2-3" totals resulting in possible incident(s) of localized
flash flooding.

DISCUSSION...Regional RADAR suite depicts a maturing MCV just
southwest of metro St. Louis lifting northeastward at this time.=20
GOES-E WV and RADAR show a broadening mid-level baroclinic
leaf/shield indicative of continued favorable evacuation aloft to
maintain the MCS for the next few hours. VWP and RAP analysis
denote the broad divergence is supporting strengthening low level
flow with solid confluence at the nose of the deeper layer
moisture axis. CIRA LPW shows corridor of 850-500mb moisture is
aligned ideally with the southwesterly flow but sfc to 850mb
moisture is very broad and increasing to support TPW value in
excess of 1.5". The 30-35kts of 850-700mb confluent flow in this
moisture regime will support 1.5-1.75" rainfall production even
with reducing/narrowing unstable axis (generally 500-750 J/kg of
MUCAPEs). The MCV is also providing a corralling of downstream
flow into a well defined deformation axis that is generally
parallel to the deeper layer steering. This orientation will be
the supportive requirement for increased duration to support
localized steaks of 2-3" totals.

Unlike further north, the ground conditions are much drier due to
the prolonged drought. Yet, FFG values of 1.5-2"/hr and 2-3"/3hr
are in the realm of exceedance and while not all locations will be
exceeded there should be a few areas that may lead to localized
flash flooding conditions through the early overnight period. As
such, flash flooding is considered possible across central IL back
through east-central MO; with slightly higher potential in the
urban areas near Metro St. Louis, due to hydrophobic grounds and
drainage.=20

Gallina

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!_WoxM95G8ExX39lGSpA8s-H7qn-FUCdGbkYh4vn_8BhypuFWDWSIc__7RJp008JX_uhC= d3_AwawJzGwp-3qEB59Qe3Q$ for graphic product...

ATTN...WFO...ILX...LSX...PAH...SGF...

ATTN...RFC...KRF...MSR...ORN...TIR...NWC...

LAT...LON 40338843 39928763 39148773 38638840 37699014=20
37499135 37969181 38549157 38819130 39579024=20
40138941=20

=3D =3D =3D
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AWUS01 KWNH 160444
FFGMPD
MOZ000-ARZ000-OKZ000-KSZ000-160845-

Mesoscale Precipitation Discussion 0113
NWS Weather Prediction Center College Park MD
1243 AM EDT Thu Apr 16 2026

Areas affected...Northeast Oklahoma...Southwest Missouri...Adj.
Northwest Arkansas...

Concerning...Heavy rainfall...Flash flooding possible

Valid 160445Z - 160845Z

SUMMARY...A few more hours of potential localized flash flooding
due to slow moving/training thunderstorms across the Ozark Plateau.

DISCUSSION...GOES-E 10.3um IR and regional RADAR mosaic shows a
solid warming/weakening trend to the convective line across much
of the Ozark Plateau. RAP analysis shows warming low levels and
increasing CINH trends across the remaining well of 1000-2000 J/kg
of MLCAPE, the exception remaining along the upwind edge across NE
OK; and this is where the healthiest updrafts remain. Still,
KINX/KSGF show most are starting to have dominating outflow
patterns. However, as the dry-line retreated and the mean
upper-level shortwave trough across IA is kicking east; a weakness
in the overall mid-level flow/steering is lying perpendicular to
weakening but sufficient southerly surface to boundary layer/925mb
flow providing solid moisture flux convergence in proximity to the
remaining MLCAPE axis. Tds in the upper 60s to low 70s. With this
convergence and steering flow parallel to the boundary (and
slacking), training or increased downdraft residency may allow for
a narrow axis of enhanced rainfall rates up to 1.75"/hr for a
potential of localized 2-3" total. Beside naturally lower FFG
due to complex terrain across the Ozark Plateau, even further west
into NE OK, FFG values are locally lower with hourly values less
than 1.5-2" and 3" values less than 3". So an isolated incident
or two of flash flooding remains possible more likely over the
next few hours (through 06z) than into late overnight hours.

Gallina

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!-TvB5wH1yA2rEBw5_ycJhpkLeoKNTS-Ovu9k5jlIx-qJ2pkeb0t11tRXvyqCe5r2sRyr= ukq0ka5--mZ0V5dP_wCKRGU$ for graphic product...

ATTN...WFO...SGF...TSA...

ATTN...RFC...KRF...MSR...ORN...TUA...NWC...

LAT...LON 37839174 37359132 36779169 36529332 36329416=20
36139587 36179651 36579663 36769627 36979505=20
37359379 37769264=20

=3D =3D =3D
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AWUS01 KWNH 162003
FFGMPD
ILZ000-MOZ000-170001-

Mesoscale Precipitation Discussion 0114
NWS Weather Prediction Center College Park MD
401 PM EDT Thu Apr 16 2026

Areas affected...a small part of Missouri

Concerning...Heavy rainfall...Flash flooding possible

Valid 162001Z - 170001Z

Summary...Isolated, slow-moving thunderstorms could cause
localized flash flooding for the next few hours (through 00Z/7p
central).

Discussion...A localized cluster of thunderstorms has become
established across central Missouri. The storms have developed in
response to strong insolation/surface destabilization beneath a
very cold mid/upper wave (-18C at 500 hPa). The storms are also
in a very localized area where mid-level flow drops off
substantially, with right-moving storm motions falling to around
5-10 knots per point forecast soundings. This explains recent
behavior of the storm cluster very near Osage Beach, MO, where
MRMS estimates of 1+ inch/hr in that area were already exceeding
local FFG.

Given the weak forcing for ascent, convective coverage is in
question. Persistence of ongoing activity - or perhaps additional
slow-moving cluster(s) of convection could produce 1 inch/hr rain
rates at times. Again, these rates could exceed FFG, and given
sensitive local terrain in the region, another instance or two of
flash flooding cannot be completely ruled out. This risk will
likely be diurnally driven and lessen some after sunset.

Cook

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!-ObucWhVuhSJtJ-DCrbSpVcGeYPrECRaPTiEJb1XmBzxTkejYnTMq5FUaz6gFsNiaqkA= M_oO_IyUC9okdjLdiTlDbSA$ for graphic product...

ATTN...WFO...EAX...LSX...PAH...SGF...

ATTN...RFC...KRF...MSR...ORN...NWC...

LAT...LON 38919228 38839074 38279022 37459022 37119109=20
37199248 37689329 38099339 38809317=20

=3D =3D =3D
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AWUS01 KWNH 171811
FFGMPD
WIZ000-ILZ000-MOZ000-MNZ000-IAZ000-180010-

Mesoscale Precipitation Discussion 0115
NWS Weather Prediction Center College Park MD
210 PM EDT Fri Apr 17 2026

Areas affected...Northeast MO...Western and Northern IL..Eastern
IA...Far Southeast MN...Central and Southern WI

Concerning...Heavy rainfall...Flash flooding likely

Valid 171810Z - 180010Z

SUMMARY...Rapid convective development is expected over highly
saturated soils this afternoon. Anomalous moisture and instability
will support rainfall rates of 1 to 2 inches/hour. While
individual cell motions will be fast, cell-training will lead to
localized totals of 2 to 4 inches, making flash flooding likely
given the sensitive antecedent conditions.

DISCUSSION...GOES-E Day Cloud Phase RGB satellite imagery and
surface observations indicate rapid destabilization across the
Upper Midwest ahead of an ejecting upper-level trough and
approaching strong cold front. A 40 to 50+ kt southwesterly
low-level jet is fostering intense warm air advection and moisture
transport into the region, resulting in an anomalously moist and
unstable airmass for mid-April (PWATs climbing to ~1.25 inches and
MLCAPE of 1500 to 3000 J/kg).

Convective initiation is expected imminently as the cap erodes,
particularly near surface waves analyzed over north-central IA and
southeast MN which are locally enhancing convergence. Deep-layer
ascent will continue to increase this afternoon and evening as a
strong shortwave/jet streak rounds the base of the trough and
approaches from the west. Convective mode is expected to feature a
mix of supercells and organized multicell clusters.

While strong deep-layer shear (40 to 50+ kts) will promote fast
individual cell motions to the northeast, the southwesterly
steering flow is largely parallel to the low-level jet axis and
lifting warm front. This alignment will strongly favor corridors
of cell-training and repeating rounds of heavy rainfall over the
same areas. High-efficiency updrafts will be capable of producing
1 to 2 inch/hour rainfall rates, with the 12Z HREF signaling
localized swaths of 2 to 4 inches through 00Z.

The primary driver for the flash flood threat is the highly
sensitive antecedent conditions. Recent NASA SPoRT 0 to 10 cm soil
moisture data indicates very moist if not saturated soils (80 to
100%) across much of the region, and USGS streamflow networks show
running waterways are already elevated. With minimal infiltration
capacity, the intense 1 to 2 inch/hour rates will to convert to
enhanced runoff concerns, and likely promoting scattered areas of
flash flooding which will include some localized urban impacts as
well.

Orrison

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!9hjs2Z_oHmyo18eoaSQu7i3KoZD9Delq5_o_Aeyu83kiVMQIawM1h87TuD-4LEItpLhN= MhaDX-LNgGe5ulc54SN8dxk$ for graphic product...

ATTN...WFO...ARX...DLH...DMX...DVN...EAX...GRB...ILX...LOT... LSX...MKX...MPX...

ATTN...RFC...KRF...MSR...NWC...

LAT...LON 45659058 45318891 44168851 42578857 41148902=20
40108946 39429028 39319154 39769277 40559338=20
41339334 43079263 44399214 45129163=20

=3D =3D =3D
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AWUS01 KWNH 171904
FFGMPD
MOZ000-OKZ000-KSZ000-NEZ000-180102-

Mesoscale Precipitation Discussion 0116
NWS Weather Prediction Center College Park MD
303 PM EDT Fri Apr 17 2026

Areas affected...portions of southern and eastern Kansas into
northwestern Missouri

Concerning...Heavy rainfall...Flash flooding possible

Valid 171902Z - 180102Z

Summary...Flash flooding is possible as storms expand in coverage
and intensity across the discussion area through 00Z/7p central.

Discussion...Convective initiation has occurred in earnest along a
synoptic front extending from near St. Joseph, MO to near Wichita,
KS over the past half hour. The storms are in an extremely
unstable environment, with 2000-3000 J/kg MLCAPE and 1.2-1.5 inch
PW values supporting heavy rainfall. The front and initial
convection was also oriented parallel to deep southwesterly
steering flow aloft, suggestive of areas of training as storms
mature over the next 1-2 hours. The localized training (and
perhaps cell mergers where individual cells can move right of mean
flow) should result in a few spots of 1.5 inch/hr rain rates that
could result FFG exceedance and flash flooding with time.

Trends through the night will ultimately depend on the degree of
convective coverage and any upscale growth into linear segments
that could materialize. Even if the dominant storm mode becomes
linear, local training axes are likely to materialize and enhance
flash flood risk. These trends, along with any potential
development out ahead of the main frontal band, will be monitored
for any corridors of significant flash flood potential through the
evening hours.

Cook

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!_6urUHJHWAXBLoWXgUTS01fJG-k_8qnlfcUOHJLu-Nf-cVPdz3_l-tPy6jQQo3CpjNI9= 066vCnaiDF9ytCYfuFMT224$ for graphic product...

ATTN...WFO...DDC...EAX...ICT...OAX...OUN...SGF...TOP...

ATTN...RFC...KRF...TUA...NWC...

LAT...LON 40579404 40529265 39909261 37869402 37089542=20
36999727 37289839 38509719 40219524=20

=3D =3D =3D
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AWUS01 KWNH 172337
FFGMPD
MIZ000-INZ000-WIZ000-ILZ000-IAZ000-180434-

Mesoscale Precipitation Discussion 0117
NWS Weather Prediction Center College Park MD
735 PM EDT Fri Apr 17 2026

Areas affected...central/northern Illinois, much of Wisconsin,
upper Peninsula of Michigan, western Indiana

Concerning...Heavy rainfall...Flash flooding likely

Valid 172334Z - 180434Z

Summary...Flash flood potential continues especially across
Wisconsin and northern Illinois. This threat will shift eastward
through the evening hours.

Discussion...A mix of linear and clustered convection continues to
migrate east/northeastward across the discussion area. Areas of repeating/training were noted across far southern Wisconsin - and
that area remains sensitive from prior heavy rainfall over the
past several days. FFGs near/downstream of ongoing convection in
southern Wisconsin are in the 1 inch/hr range (locally lower),
with urban impacts from heavy rain expected in the Milwaukee area
over the next 1-2 hours or so. Flash flooding remains likely
there.

Farther north, scattered convection has matured over central
Wisconsin just ahead of a synoptic cold front despite widespread
convective overturning. Instability profiles remain supportive of
strong/deep convection in the short term (next couple hours),
though the longevity of this convection is in question with
eastward extent. Nevertheless, widespread impacts from recent
heavy rain, swollen watersheds, and snow melt have left the region
very sensitive (FFGs near 0 in the UP of Michigan, also <1 inch/hr
elsewhere in parts of northeastern Wisconsin), and localized flash
flooding remains possible.

Cells in the southern part of this elongated conpmex (exiting
southeastern Iowa) are more linear in nature, though a few cells
have developed over west-central Illinois that should merge with
this line over the next few hours. Ground conditions aren't as
sensitive in central Illinois compared to farther north. Flash
flooding may be more isolated/dependent on local rain rate
enhancement from these mergers.

Eventually, this elongated complex will shift eastward through
northeastern Illinois and into western Indiana, with at least
isolated flash flood potential continuing through 05Z/midnight
central.

Cook

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!75sQHgPWBmHMjZ1Iw9XEB_ZKL_6aH3-pygDpV2_kNNOuyft9zc_2YNqGB8JtW2UbmLfK= YzgLHaEoDJkopQwKKRSvHJA$ for graphic product...

ATTN...WFO...ARX...DLH...DVN...GRB...ILX...IND...IWX...LOT... LSX...MKX...MQT...

ATTN...RFC...MSR...TIR...NWC...

LAT...LON 46768913 46698706 46338613 44718704 42648721=20
41438661 40218642 39408761 39449008 40039107=20
40969098 42259046 43959061 45999024=20

=3D =3D =3D
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AWUS01 KWNH 172339
FFGMPD
MIZ000-INZ000-WIZ000-ILZ000-IAZ000-180434-

Mesoscale Precipitation Discussion 0117
NWS Weather Prediction Center College Park MD
738 PM EDT Fri Apr 17 2026

Areas affected...central/northern Illinois, much of Wisconsin,
upper Peninsula of Michigan, western Indiana

Concerning...Heavy rainfall...Flash flooding likely

Valid 172334Z - 180434Z

Summary...Flash flood potential continues especially across
Wisconsin and northern Illinois. This threat will shift eastward
through the evening hours.

Discussion...A mix of linear and clustered convection continues to
migrate east/northeastward across the discussion area. Areas of repeating/training were noted across far southern Wisconsin - and
that area remains sensitive from prior heavy rainfall over the
past several days. FFGs near/downstream of ongoing convection in
southern Wisconsin are in the 1 inch/hr range (locally lower),
with urban impacts from heavy rain expected in the Milwaukee area
over the next 1-2 hours or so. Flash flooding remains likely
there.

Farther north, scattered convection has matured over central
Wisconsin just ahead of a synoptic cold front despite widespread
convective overturning. Instability profiles remain supportive of
strong/deep convection in the short term (next couple hours),
though the longevity of this convection is in question with
eastward extent. Nevertheless, widespread impacts from recent
heavy rain, swollen watersheds, and snow melt have left the region
very sensitive (FFGs near 0 in the UP of Michigan, also <1 inch/hr
elsewhere in parts of northeastern Wisconsin), and localized flash
flooding remains possible.

Cells in the southern part of this elongate complex (exiting
southeastern Iowa) are more linear in nature, though a few cells
have developed over west-central Illinois that should merge with
this line over the next few hours. Ground conditions aren't as
sensitive in central Illinois compared to farther north. Flash
flooding may be more isolated/dependent on local rain rate
enhancement from these mergers.

Eventually, this elongated complex will shift eastward through
northeastern Illinois and into western Indiana, with at least
isolated flash flood potential continuing through 05Z/midnight
central.

Cook

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!9U-h3PbHAPaEvnkDE8b8ojujiT2ikJcvFmDdocidQB9F7rW9CG0HfjZD7aSshrypXflm= 0uVx1ZhowZi6PlF2XOrL6hQ$ for graphic product...

ATTN...WFO...ARX...DLH...DVN...GRB...ILX...IND...IWX...LOT... LSX...MKX...MQT...

ATTN...RFC...MSR...TIR...NWC...

LAT...LON 46768913 46698706 46338613 44718704 42648721=20
41438661 40218642 39408761 39449008 40039107=20
40969098 42259046 43959061 45999024=20

=3D =3D =3D
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AWUS01 KWNH 180043
FFGMPD
ILZ000-MOZ000-ARZ000-OKZ000-KSZ000-180641-

Mesoscale Precipitation Discussion 0118
NWS Weather Prediction Center College Park MD
842 PM EDT Fri Apr 17 2026

Areas affected...northern/central/eastern Oklahoma, southeastern
Kansas, southern/central Missouri, northwestern Arkansas

Concerning...Heavy rainfall...Flash flooding possible

Valid 180041Z - 180641Z

Summary...Isolated instances of flash flooding remain possible
through 06Z/1a central.

Discussion...Ongoing convection has largely organized into an
extensive linear complex extending from near Osage Beach, MO
west-southwestward through Ponca City and Gage, OK. The storms
are mostly undercut by composite synoptic front/outflow, although
a few elements in central Missouri and far north-central Oklahoma
remain surface-based. The storms are migrating eastward between
35-45 knots while exhibiting localized training and areas of 1-2
inch/hr rain rates at times. These rates should be enough for
isolated flash flooding as FFG thresholds are generally in the
1-1.5 inch/hr range especially from north-central Oklahoma
eastward.

Storms will be maintained through the overnight hours by abundant
instability (1000-2500 J/kg MLCAPE) and strengthening low-level
flow oriented perpendicular to the aforementioned front/outflow,
maintaining robust updrafts and occasional training. Cells may
tend to weaken some in east-central Missouri, but re-development
over western Oklahoma near a front/dryline intersection should
maintain the heavy rain risk through at least 06Z/1a central
tonight. Flash flooding is expected on at least an isolated basis
where training is most pronounced, with terrain influences in
southwestern Missouri also likely playing a role in enhancing
flash flood risk. Lastly, models suggest that the ongoing
convective band will gradually develop southeastward toward the
I-40 corridor in Oklahoma through the night.

Cook

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!8uiQ__KyH0yp5gD3LVLtiqN8N1vgyEat01kFbc0VsJSyK8Qphlh3hQqt4IJgyiwUMQIe= xQ9i_b7j_xr2DclgdMvU51Y$ for graphic product...

ATTN...WFO...EAX...ICT...LSX...LZK...OUN...PAH...SGF...TOP...
TSA...

ATTN...RFC...KRF...MSR...ORN...TUA...NWC...

LAT...LON 39309207 38969054 37709043 36569135 35499386=20
34529681 34489883 35219970 36259956 36939828=20
37899631 38929406=20

=3D =3D =3D
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AWUS01 KWNH 181945
FFGMPD
LAZ000-TXZ000-190145-

Mesoscale Precipitation Discussion 0119
NWS Weather Prediction Center College Park MD
344 PM EDT Sat Apr 18 2026

Areas affected...Southeast TX...Southwest LA

Concerning...Heavy rainfall...Flash flooding possible

Valid 181945Z - 190145Z

SUMMARY...Potent thunderstorms capable of producing >2"/hr
rainfall rates over the urbanized communities of southeast TX and
southwest LA could cause localized urban flash flooding.

DISCUSSION...Visible satellite and Doppler Radar show a bubbling
field of convection over southeast TX and southwest LA in advance
of an approaching strong cold front. Additional surface based
heating this afternoon will yield over 1,500 J/kg of MLCAPE along
the I-10 corridor. Winds in advance, and in wake, of the cold
front are NErly while winds within the 700-200mb layer are firmly
out of the WSW. This is supporting effective bulk vertical wind
shear levels that the RAP suggests could surpass 40 kts. This
would allow for thunderstorms to have more longevity than typical
"pop-up" or "garden variety" storms. HRRR and RAP area averaged
soundings show warm cloud layers up to 12,000ft deep and skinny
CAPE profiles that found in typical warm rain processes. As 850mb
and 700mb weaken over the region this evening, the concern is for
additional thunderstorm development either along the cold front or
induced by the growing cold pool.

Given the favorable thermodynamic environment and increasing PWs
that reach 2.0" east of Houston this evening, the concern is for

2"/hr rainfall rates that manifest over urbanized environments.

The 12Z HREF does show low-chance probabilities (10-30%) from the
Houston suburbs on east into southwest LA this afternoon and
evening. The vast majority of the expected rainfall over southeast
TX and southwest LA this afternoon is welcomed (severe and extreme
drought for many), which is also evident in the 1-hr FFGs that are
no lower than 2" area wide. That said, the potential for
slow-moving and repeating rounds of storms, combined with
anomalous PWs and ample instability aloft, could cause localized
flash flooding in urbanized settings that contain a greater
concentration of hydrophobic surfaces. Low-lying areas with poor
drainage are also susceptible to flash flooding this afternoon.

Mullinax

...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!9x_hjSr_ftys34SFugzCvxjT-H0aqr-0ltdAUpbxeqrkiGilLjiBwS_-XpRE3GUtr1g_= A55YawAS8oeq-cWzDYFgzAg$ for graphic product...

ATTN...WFO...HGX...LCH...

ATTN...RFC...FWR...ORN...NWC...

LAT...LON 30589389 30569330 30069327 29629387 29209491=20
28939574 28839638 28939668 29259658 29709602=20
30369451=20

=3D =3D =3D
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