FOUS30 KWBC 270206 CCA
QPFERD

Excessive Rainfall Discussion...CORRECTED
NWS Weather Prediction Center College Park MD
906 PM EST Fri Dec 26 2025

Day 1
Valid 01Z Sat Dec 27 2025 - 12Z Sat Dec 27 2025

Corrected for geographical typo in Day 1

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF CALIFORNIA MAINLY FOR THIS EVENING...

0100Z Update...
With radar continuing to show decreasing coverage and intensity of
rainfall across California and decreasing signals from the HREF=20 probabilities for rainfall exceeding 1- and 3-inch amounts=20
exceeding flash flood guidance...have opted to downgrade from a=20
Slight Risk area to a Marginal Risk area. Reported rainfall rates=20
and those derived by radar have been decreasing during the late=20
afternoon with only isolated spots realizing 0.25 inches per 3=20
hours. Given how water-logged some places have become over the=20
past couple of days...any additional rainfall has the potential to
result in new flooding/run off concerns or at least prolong the=20
amount of time needed to drain off existing floodwater. On the=20
other hand...given the recent AEP values have been less than=20
impressive during the afternoon and the diminishing coverage of=20
rainfall rates and coverage of rainfall...removed the Slight risk=20
but kept the Marginal risk area where a moisture plume remained=20
with the expectation that loss of daytime heating will further aid
the reduction of rainfall rates and areal coverage.

Bann

1600Z Update...

The Marginal Risk area has been expanded north to include much of
northern CA, including the coastal ranges, Bay Area, and northern
portions of the Central Valley. The arrival of a fairly strong
500/700 mb low center just offshore will be driving areas of heavy
showers going through the afternoon hours. While this energy will
be generally weakening with time, the addition of at least modest
boundary layer heating along with some steepening of the mid-level
lapse rates should favor some convective elements capable of
producing localized rainfall rates of 0.50" to 0.75"/hour. Some
localized additional rainfall totals of 1 to 2 inches will be
possible, and especially across the northwest CA coastal range.
These additional rains may foster some additional localized
runoff concerns given the wet/saturated soil conditions and=20
elevated streamflows. No changes have been made to the Slight Risk=20
area farther south across southern CA as the threat of heavy rain=20
will continue here into at least the early evening hours.

Orrison


Previous discussion...

Few changes were needed for this morning's update. A positively-
tilted upper level trough will push ashore and inland across the
Pacific Northwest today. This will keep the flow at all levels
unidirectional out of the southwest across Southern California, on
the leading edge of a 140 kt jet. As the trough pushes east, less
and less of it will be over the Pacific, resulting in a diminishing
of the onshore flow with time. Waves of rainfall will push ashore
into southern California through the day. Lingering instability
will support rates that may be heavy at times. This is most likely
as the storms interact with the terrain of the eastern Transverse
Ranges, from L.A. north and east. It is in this area that the
rainfall forecast peaks at around 3 inches at the highest
elevations. Meanwhile most of the L.A. Basin picks up another 1-2
inches. 1-2 inches of rain would be problematic on a normal day,
but following multiple days of multiple inches of rain per day,
making the 1-2 inches expected today lighter by comparison...expect
scattered instances of flash flooding to redevelop again today.
While all areas of coastal Southern California and the Los Angeles
basin will pick up some rain, those highest totals will be north
and east of the downtown area. Thus, from downtown L.A. north and
east, a higher end Slight is in effect. The flooding impacts will
be the result of continued drainage of prior rainfall over
Christmas Eve and Day, as well as urban effects. A Moderate Risk
may need to be considered from Pasadena east through San Bernardino
if rainfall amounts exceed expected totals.

Elsewhere, the Slight remains in place down the coast to about San
Diego, as the eastward moving bands of rain impacting the L.A.
Basin should struggle to continue further south. Meanwhile the
Marginal for limited shower activity and/or lowering snow levels in
the foothills of the Sierra Nevada remains in place unchanged with
this update. For Central and Northern California, it's probable
that there will be more total precipitation in these parts of the
state compared to further south, but because of lowering snow
levels due to cold air influx with the aforementioned trough
moving in, much of it should fall as snow at the higher elevations,
reducing the flooding threat downstream.

By this evening, the flow will flip around to the northwest,
ushering in drier air and finally ending the rainfall threat across
Southern California likely for the rest of 2025.

Wegman

Day 2
Valid 12Z Sat Dec 27 2025 - 12Z Sun Dec 28 2025

The probability of rainfall exceeding flash flood guidance is less
than 5 percent.

Santorelli

Day 3
Valid 12Z Sun Dec 28 2025 - 12Z Mon Dec 29 2025

The probability of rainfall exceeding flash flood guidance is less
than 5 percent.

An area of rainfall across much of the Midwest is expected with a
developing low moving into the Great Lakes. The combination of
prior dry soil conditions, rapid movement, poor instability, and
cold air following the rain should all work to keep this event
largely beneficial. Flooding concerns in this area at this time
are too low for even a marginal risk.

Santorelli/Wegman


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!8Xs7kvA94gMOKx_Qtm2QhI4P-4myh6917pS8E_A0k0QX= F3kCp1QvESYEnMuQr5YwVmAUgCWwNX5eYg-1GogyIFGPpZM$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!8Xs7kvA94gMOKx_Qtm2QhI4P-4myh6917pS8E_A0k0QX= F3kCp1QvESYEnMuQr5YwVmAUgCWwNX5eYg-1GogyM5v2eCI$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!8Xs7kvA94gMOKx_Qtm2QhI4P-4myh6917pS8E_A0k0QX= F3kCp1QvESYEnMuQr5YwVmAUgCWwNX5eYg-1Gogy9BPPAgY$=20

=3D =3D =3D
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FOUS30 KWBC 052011 CCA
QPFERD

Excessive Rainfall Discussion...CORRECTED
NWS Weather Prediction Center College Park MD
311 PM EST Mon Jan 5 2026

Day 1
Valid 16Z Mon Jan 05 2026 - 12Z Tue Jan 06 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ALONG THE CENTRAL
TO NORTHERN CALIFORNIA COAST AND NORTHERN CALIFORNIA...

...16Z update...

The forecast reasoning in the previous discussion remains valid and
only minor adjustments were made to the existing Marginal Risk
across north-central California. The primary shortwave embedded
within the longwave trough in the eastern Pacific was centered near
128W and will advance closer to the north-central California coast
between Point Arena and San Francisco Bay through 00Z. After 00Z,
the closed mid-level low will elongate and weaken as it moves
southward offshore of the coast. There is good model agreement in
this forecast and the corresponding low level wind field becoming
largely parallel to the central California coast overnight while
weakening.

The main concern for heavy rain related impacts will be prior to
03Z Tuesday where isolated hourly rainfall of 0.50 to 0.75 inches
primarily focused along the Coastal Ranges toward the San Francisco
Bay region later today with isolated hourly totals near 1 inch
possible. East of the Coastal Ranges, peak hourly rainfall up to
~0.50 inches is expected. Additional peak rainfall through 12Z
Tuesday will be in the 2-4 inch range

Otto

...previous discussion follows...


Upper disturbance off the California coast will meander to the
southeast closer to the coastal plain, eventually pinching off the
mean trough centered to the north and closing off into an ULL as it
migrates down near the latitude of the Bay area. Proximity of the
disturbance and prevailing flow will send a modest IVT pulse
(300-400 kg/ms) crashing into the northern CA coastal plain with
some minor protrusion of the IVT signature inland with a secondary
QPF maxima forecast around the Trinity Mountains over into Shasta
National Forest domain. Hi-res deterministic output is pretty
consistent with the axis of heaviest precip focused from the King
Range down towards Santa Rosa, north of the Bay area with the
latest HREF EAS probs for 1" running between 60-90% for much of
that location with another prob max focused near Mount Shasta.

The main threat for this setup is easily over any urbanized zones
and remnant burn scars across northern CA leading to mainly a
lower-end flash flood concern in the grand scheme of the setup. IVT
signature is one that historically yields more isolated flash flood
threats with the primary focus typically aimed at that coastal
urban centered from the Bay area up towards Eureka, and over the
northern valley locations like Redding. This is where the MRGL
risk was maintained during the forecast as the trend for the
southern edge of any heavy rain prospects south of San Jose has all
but disappeared on guidance. It's still something we'll monitor
for any last minute trends back, but guidance favors mainly the
area north of the Bay at this time. Total QPF for the impacted
areas will be between 1.5-3" with a max between 4-5" for the
coastal ranges north of the Bay area, and over the Shasta National
Forest.

Kleebauer


Day 2
Valid 12Z Tue Jan 06 2026 - 12Z Wed Jan 07 2026

The probability of rainfall exceeding flash flood guidance is=20
less than 5 percent.

Fracasso


Day 3
Valid 12Z Wed Jan 07 2026 - 12Z Thu Jan 08 2026

The probability of rainfall exceeding flash flood guidance is=20
less than 5 percent.

Fracasso


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!6iQ4L-UbvWDSw4dGlZLIfuz2wLaBHsz6i675pOOl0HeF= nq7UiRCdn2XTQTHlvTZRPJiEnuuUJnUpGJUOw-ddO03kBpQ$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!6iQ4L-UbvWDSw4dGlZLIfuz2wLaBHsz6i675pOOl0HeF= nq7UiRCdn2XTQTHlvTZRPJiEnuuUJnUpGJUOw-dduFdKZ8M$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!6iQ4L-UbvWDSw4dGlZLIfuz2wLaBHsz6i675pOOl0HeF= nq7UiRCdn2XTQTHlvTZRPJiEnuuUJnUpGJUOw-dd2gUpZv8$=20

=3D =3D =3D
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FOUS30 KWBC 120831 CCA
QPFERD

Excessive Rainfall Discussion...CORRECTED
NWS Weather Prediction Center College Park MD
331 AM EST Thu Feb 12 2026

Day 1
Valid 12Z Thu Feb 12 2026 - 12Z Fri Feb 13 2026

The probability of rainfall exceeding flash flood guidance is less
than 5 percent.

Putnam


Day 2
Valid 12Z Fri Feb 13 2026 - 12Z Sat Feb 14 2026

...There is a Marginal Risk of Excessive Rainfall Across Portions
of the Southern Plains on Friday...

Moist southerly flow from the Gulf will begin to increase across=20
the Southern Plains during the day Friday and especially into the=20 evening/overnight hours as a southern-stream upper-trough=20
approaches the region from the Southwest. This will help to=20
reinforce a frontal boundary left from prior shortwave(s) passage=20
with a roughly west or west-southwesterly axis from the western=20
Ozarks through Oklahoma and into northwest Texas. The late arrival=20
of an appreciable combination of increasing low level winds along=20
the boundary and height falls from the approaching upper-trough=20
should limit any storm development until after 00Z. The lack of=20
particularly notable moisture (surface dewpoints less than 60)=20
given that this will be day one of return flow as well as the onset
of night will lead to limited/elevated instability, with the=20
chance that development could also be mostly north of the quasi-=20
stationary boundary. Additionally, antecedent conditions are rather
dry suggesting initial rainfall would be mostly beneficial.=20
Nevertheless, model guidance has been consistent in depicting the=20
potential of locally heavy bouts of rainfall in the 2-2.5" range=20
which, if realized, could lead to some isolated flooding concerns=20 particularly for urban areas.=20

Putnam


Day 3=20
Valid 12Z Sat Feb 14 2026 - 12Z Sun Feb 15 2026

...There is a Slight Risk of Excessive Rainfall from the ArkLaTex=20
to Mid-South Saturday...

The upper-trough will fully emerge over the Southern Plains on=20
Saturday and progress eastward towards the Lower Mississippi Valley
by Sunday morning. Consolidating/deepening surface low pressure=20
will sweep eastward in tandem with an expected track based on the=20
latest model guidance from the Red River Valley east-northeast=20
through the Ozarks and into the Mid-South, with an eastward=20
extending warm front and trailing cold front. A strengthening low=20
level jet with an additional day of moist southerly return flow=20
from the Gulf will help to better prime the warm sector with=20
dewpoints into the 60s and some rather modest but relatively higher
instability in the 500 J/KG range.=20

Storms will likely be ongoing at the start of the period in=20
vicinity of the low and eastward along the warm front, roughly in=20
the western Ozarks vicinity, with the potential for some lingering=20
isolated flooding concerns. More potent thunderstorms capable of=20
locally heavy rainfall are expected to develop with daytime heating
southwest along the trailing cold front through the ArkLaTex and=20
into eastern Texas. Increasing wind fields aloft, deep-layer flow=20
roughly parallel to the boundary, and eastward progression of the=20
cold front will likely lead to a line of numerous, potentially=20
organized thunderstorms with training potential, increasing the=20
likelihood of some locally heavy totals. Additional storms may=20
develop ahead of the surface low track in vicinity of the warm=20
front helping to prime soils and increase totals. However, the=20
front is expected to remain progressive, which will keep an upper=20
limit on rainfall totals, particularly with southern extent. A=20
Slight Risk has been maintained from the ArkLaTex northeast into=20
the Mid-South roughly following the expected low track. While=20
antecedent conditions are generally dry, a consensus of model=20
guidance supports areal average rainfall in the 1.5-2" range, with=20
locally heavier totals of 3-4", which could still lead to some=20
scattered instances of flash flooding. The latest 00Z model=20
guidance suggests the axis of heaviest rainfall is more likely on=20
the southeastern side of the Slight Risk, but have avoided any=20
significant adjustments for now, especially outside of the hi-res=20
window.=20

Putnam


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!46NEEr1pCetZo53fznzHj33-cEYhtRPJBx1aHQ4g1drR= 2VXVqQu_UV20qOx-FZSR3yGhAcEwpFWJkI-LgdJo9q9SLxM$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!46NEEr1pCetZo53fznzHj33-cEYhtRPJBx1aHQ4g1drR= 2VXVqQu_UV20qOx-FZSR3yGhAcEwpFWJkI-LgdJofW1-6Ms$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!46NEEr1pCetZo53fznzHj33-cEYhtRPJBx1aHQ4g1drR= 2VXVqQu_UV20qOx-FZSR3yGhAcEwpFWJkI-LgdJov5d0nc0$=20

=3D =3D =3D
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FOUS30 KWBC 181944 CCA
QPFERD

Excessive Rainfall Discussion...CORRECTED
NWS Weather Prediction Center College Park MD
244 PM EST Wed Feb 18 2026

Corrected for typo in last sentence of Day 2 text

Day 1
Valid 16Z Wed Feb 18 2026 - 12Z Thu Feb 19 2026

The probability of rainfall exceeding flash flood guidance is less
than 5 percent.

Otto


Day 2
Valid 12Z Thu Feb 19 2026 - 12Z Fri Feb 20 2026

A potent mid-level shortwave/closed low is forecast to bring
another round of heavier precipitation to southern CA beginning
Thursday morning, ahead of a progressive cold front. Peak model=20
consensus of MUCAPE no greater than 250 J/kg and IVT values of=20
300-400 kg/m/s appear to be slightly weaker than what was=20
associated with the round of heavier rain which impacted the=20
Transverse Ranges early Wednesday morning. However, locally high=20
48-72 rainfall totals have impacted portions of southern CA along=20
with a number of flooding reports since Monday.

The next round to affect southern California's Transverse and=20
Peninsular Ranges is expected to bring peak hourly rainfall values
in the 0.5 to 1.0 inch range on Thursday (12Z HREF probs for=20
greater than 0.5 inches in 1 hour were 30-40 percent), from roughly
15Z/18 to 03Z/19, advancing southward along the coast with time.=20
Given the progressive nature, peak total rainfall is forecast to=20
fall in the 1 to 2 inch range for the Transverse and Peninsula=20
Ranges but could be a bit higher for the Peninsular Ranges given a=20
longer and more favorable fetch of low level moisture into the
region. While the 12Z NAM_nest is likely overdone, it does show 3+
inch potential for localized areas below snow levels which look to
briefly rise in the 5000-6000 foot range. Any flood related=20
impacts should remain isolated and minor in magnitude.

Otto


Day 3
Valid 12Z Fri Feb 20 2026 - 12Z Sat Feb 21 2026

The probability of rainfall exceeding flash flood guidance is less
than 5 percent.

Otto


Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!5N6V9V2B7mOBPkkk83gviV1QOp-KPIThnoDtotJCDSMp= Oxs1D9J8KAZl4bq-GQtCL1HCHu6xjK6pCKGFmVnr3otuy5g$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!5N6V9V2B7mOBPkkk83gviV1QOp-KPIThnoDtotJCDSMp= Oxs1D9J8KAZl4bq-GQtCL1HCHu6xjK6pCKGFmVnrzXQnRvQ$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!5N6V9V2B7mOBPkkk83gviV1QOp-KPIThnoDtotJCDSMp= Oxs1D9J8KAZl4bq-GQtCL1HCHu6xjK6pCKGFmVnrxLulBk0$=20

=3D =3D =3D
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FOUS30 KWBC 142326 CCA
QPFERD

Excessive Rainfall Discussion...CORRECTED
NWS Weather Prediction Center College Park MD
726 PM EDT Tue Apr 14 2026

Day 1
Valid 16Z Tue Apr 14 2026 - 12Z Wed Apr 15 2026

...THERE IS A SLIGHT RISK FOR EXCESSIVE RAINFALL ACROSS THE CENTRAL
L.P. OF MICHIGAN,SOUTHEAST WISCONSIN, AND THE OHIO VALLEY...

... Ohio Valley...

16Z Update: The Slight Risk for Excessive Rainfall was expanded
farther south to include central Illinois to central Indiana.Radar
and surface observations show an outflow boundary lingering across
the region from early morning showers and thunderstorms that may be
a focal point for locally heavy rainfall this afternoon and
evening. The RRFS and ARW model camps in particular are
highlighting this region with QPF maxima in the 2-5 inch range.
High seasonable PWATS and abundant instability also support the
potential for high hourly rainfall rates.

...Wisconsin and Michigan...

16z Update:

The forecast continues to support the risk for flash
flooding as storms are expected to form along a stationary boundary
over Wisconsin and then congeal into a line of storms that
progresses southeastward into Michigan. The low level jet will
transport moisture orthogonal to a stationary boundary across the
region with the training of storms possible. Most of the area
remains at near or above record spring rainfall and soils are
fairly saturated. Cells capable of 1.5-2"/hr rates and localized
totals of 2-3+" suggest the placement of a Slight Risk of Excessive
Rainfall from southern Wisconsin to eastern Michigan.

...Previous Discussion...

A Slight Risk for excessive rainfall remains
in effect for portions of the Great Lakes region. A
shortwave/vorticity center lifting out over the mean ridge in the
Great Lakes region will drive stronger confluence of the low level
jet across Iowa to trigger another round of strong to severe
thunderstorms Tuesday evening. Overall deep layer steering flow and
fairly orthogonal ascent over boundary should help to focus a
similar west to east (WNW to ENE) oriented axis of training
thunderstorms. Upper-level dual jet couplet will further enhance
up-scale growth to a broader complex to maintain through the
overnight period. Most of the area remains at near or above record
spring rainfall and soils are fairly saturated, so with cells
capable of 1.5-2"/hr rates and localized totals of 2-3+" suggest
the placement of a Slight Risk of Excessive Rainfall across
portions of eastern WI and central MI (along and north of I-94).

... Lower Trans-Pecos/Big Bend...

16 Update:

Latest model guidance indicates a higher QPF maxima across the
Lower Trans-Pecos region into the Big Bend as storms fire along the
dry line in presence of a seasonally moist environment. HREF 24
hour QPF neighborhood probabilities are around 50-70% for 2 inches
and 10-20% probabilities for 3 hour QPF exceeding flash flood
guidance. A Marginal Risk was maintained, but this area will be a
focus for locally heavy rainfall.

...Oklahoma and Kansas...

16z Update: Another targeted area for heavy rainfall will be span
south of the Norman area, northeastward into the Tulsa metro and
southern Kansas. Hi-res guidance indicates multiple rounds of
storms could traverse this region as storms fire along the dry line
boundary and south of a stationary front in Kansas. HREF 24 hour
QPF probabilities exceeding 2 inches are fairly high (50-70%) and
20-40% for exceeding 3 inches.

...Previous Discussion...
A steady stream of PW values of 1.25 to
1.5 inches will be advecting northward through the Southern/Central
Plains nearly parallel to the dryline. This will be conducive for
slow storm motion with locally heavy rainfall. Consensus suggests 3
to 4 inches possible within the isolated cells. The Marginal Risk
area is connected to the area of concern over the Great Lakes and
just note the coverage will decrease northward along the dry-line.

Campbell/Wilder


Day 2=20
Valid 12Z Wed Apr 15 2026 - 12Z Thu Apr 16 2026

...THERE IS A SLIGHT RISK FOR EXCESSIVE RAINFALL FOR THE GREAT
LAKES AND NORTHERN OHIO VALLEY..

The surface to mid-level environment remains very similar to the
past couple of days with a stark dry line extending from the Pecos
River Valley across the Southern Plains into the Upper Mississippi
Valley. A stationary front will continue to align west to east=20
from Illinois to New York and serve as a mechanism for heavy=20
rainfall potential. The longwave trough will finally be making=20
progress toward the Central Plains and the deep layer moisture axis
and instability shifts slightly eastward.

An upgrade to a Slight Risk for Excessive Rainfall was added across
southern Wisconsin and Michigan. Across the northern Ohio Valley,
northern Illinois, Indiana, and Ohio were included in the risk
area. A persistence forecast worked well here where instability,
plentiful moisture near the surface (PWATS near or exceeding 1.5=20
inches), and a nearby stationary boundary and weak area of low
pressure will help create an environment capable of producing heavy
rainfall. WPC QPF indicates 1-3 inches of rain over the same=20
regions that have have seen rounds of heavy rainfall over the past
couple of days. The flash flood guidance, meanwhile, has lowered to
a half an inch to an inch. Another consideration was the flash
flood sensitivity for urban areas such as Milwaukee, Chicago, and
Detroit. The Slight Risk does extend southward across northern Illinois
and Indiana to account for uncertainty on storm track and the
spread of 2 inch HREF 24 hr QPF neighborhood probability.=20

...Eastern Oklahoma and the Ozarks...

Similar to the past couple of days, afternoon storms are likely to
form and trek from the southwest to northeast ahead of the=20
longwave trough moving into the Central Plains. Eastern Oklahoma
into the Ozarks will be in the right entrance of the jet streak,
which will help provide lift. At the surface, high PWATS and
surface instability will once again prime the atmosphere for hourly
rainfall rates of an inch/hr. QPF guidance does show a maximum of
1-2 inches across the region, but model guidance shows little to=20
no probability for accumulations exceeding 2 inches. Therefore, a=20
Marginal Risk is maintained for the risk area. Additionally, the=20
more flash flood prone Ozark mountain range is relatively dry.=20

...Northeast...

A Marginal Risk for Excessive Rainfall was expanded eastward across
New York State to Connecticut. Moisture transport will increase=20
across the east as the longwave trough shifts eastward into the=20
center of the country. Additionally, weak areas of low pressure=20
will ride along a stationary boundary across the Northeast that=20
will help funnel moisture across the area. Remnants of the storms=20
across the Great Lakes may bring a round of showers and storms in=20
the morning, followed by another round of heavier showers and=20
thunderstorms in the afternoon. Model guidance shows a corridor of
1-1.5 inches rainfall with embedded higher amounts depending on the
model. The relatively lower flash guidance across western=20
Pennsylvania and the more urban footprint of areas such as=20
Connecticut and New England also help confidence of expanding the=20
Marginal eastward.=20

Wilder

Day 3
Valid 12Z Thu Apr 16 2026 - 12Z Fri Apr 17 2026

The probability of rainfall exceeding flash flooding guidance is
less than 5 percent.

Wilder

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!6qXprxWInP10H82QZ3A_xooVfjJN2HoH071NgRtdUcSx= r4T3NS7mDIMxk1Az7UvSBFBrZeFZcKQQtvc0YkOag5imW-s$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!6qXprxWInP10H82QZ3A_xooVfjJN2HoH071NgRtdUcSx= r4T3NS7mDIMxk1Az7UvSBFBrZeFZcKQQtvc0YkOaQuV7rU8$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!6qXprxWInP10H82QZ3A_xooVfjJN2HoH071NgRtdUcSx= r4T3NS7mDIMxk1Az7UvSBFBrZeFZcKQQtvc0YkOacvSSPBM$=20

=3D =3D =3D
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