ACUS01 KWNS 201339
SWODY1
SPC AC 201338

Day 1 Convective Outlook RESENT 1
NWS Storm Prediction Center Norman OK
0838 AM CDT Wed Aug 20 2025

Valid 201300Z - 211200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
TEXAS/DEEP SOUTH AND NORTHERN PLAINS...

...SUMMARY...
Scattered thunderstorms from Texas across the Lower Mississippi
Valley and Gulf Coast states may pose a risk for localized damaging
wind gusts this afternoon and evening. Isolated severe thunderstorms
may also occur across eastern Montana and northern North Dakota.

...Texas to Lower Mississippi Valley/Gulf Coast States...
A convectively augmented effective front will continue to progress
southward, southward-shifting the potential for microburst-related
wind damage regionally. Diurnal heating of a moist boundary layer
will result in a moderately to strongly unstable and weakly capped
airmass by afternoon, with the strongest buoyancy (2500+ J/kg
MLCAPE) expected across central/east Texas east-northeastward to Mississippi/western Alabama/southern Tennessee. Some small-scale
clusters may evolve, but weak vertical shear will otherwise tend to
keep the overall pulse-type damaging wind potential very isolated.

...Northern Plains...
The region will be influenced by late-day/nighttime height falls as
a shortwave trough emerges eastward from the Canadian Rockies, with
an eastward-advancing cold front moving across eastern Montana into
North Dakota tonight. A narrow corridor of moderate to large
buoyancy is expected along/ahead of the surface cold front, and near
a pre-frontal surface trough. Beneath a plume of warm elevated
mixed-layer air, mid/upper-level support for the initiation of
boundary-layer based thunderstorm development is forecast to
generally remain north of the international border.

One exception may be in the post-frontal environment across eastern
Montana. The environment would be conducive to a few severe storms
capable of hail/wind. While the risk for severe thunderstorms
appears largely conditional into North Dakota where stronger
destabilization is expected, isolated deeper convective development
is plausible across northwestern North Dakota in proximity to the
surface low/front late this afternoon, and more so this evening.
Should this occur, forecast soundings indicate the environment would
support isolated supercell development and related severe-weather
risks.

..Guyer/Marsh.. 08/20/2025

$$

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ACUS01 KWNS 241216
SWODY1
SPC AC 241215

Day 1 Convective Outlook RESENT 1
NWS Storm Prediction Center Norman OK
0715 AM CDT Sun Aug 24 2025

Valid 241300Z - 251200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE
SOUTH-CENTRAL PLAINS AND NORTHEAST...

...SUMMARY...
A few severe storms are expected this afternoon and evening across
the south-central High Plains spanning eastern Colorado into western
Oklahoma. Scattered strong to severe storms are also possible across
portions of Pennsylvania and New York.

...South-central High Plains..
Within an amplified upper flow regime, a moderately strong belt of northwesterly winds aloft will exist over the region, with one or
more low-amplitude ridge-peripheral disturbances expected to pivot
eastward later today over the central Rockies. A pronounced surface
anticyclone will settle into the northern Plains, forcing the
leading edge of more continental air into the southern Plains by the
end of the period. A corridor of low-level warm advection will
become established from southern Wyoming into western Oklahoma
coincident with the northwest/southeast-oriented front.

Widely scattered generally non-severe elevated storms will probably
persist this morning across western Kansas, with some potential that
the storms may help focus some renewed/increasing convective
potential later today from southwest Kansas into western
Oklahoma/eastern Texas Panhandle. Aided by increasing low-level
upslope flow, other potentially severe storms are expected to
develop across the Colorado Front Range vicinity by late afternoon
and drift southeastward through early/mid-evening. A couple of
supercells will initially be possible, before storms tend to cluster
by evening. Large hail and damaging winds are the primary concerns
regionally, although current thinking is that overall potential
should remain relatively isolated.

...Northeast including New York/Pennsylvania...
A prominent upper-level trough over Ontario/Quebec and Great Lakes
will shift eastward today. An associated surface front is forecast
to advance into western portions of New York/Pennsylvania by early
afternoon. Modest boundary-layer heating is expected to aid
destabilization ahead of the front and convective temperatures
should be breached by around 20-21z; although, deep-layer lapse
rates are not expected to be particularly steep (0-6 km values
around 6.5 C/km). These storms could generate locally strong winds,
and perhaps some hail, with the main risk from mid-afternoon into
early evening.

..Guyer/Kerr.. 08/24/2025

$$

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