ACUS01 KWNS 211240
SWODY1
SPC AC 211239

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0739 AM CDT Tue Apr 21 2026

Valid 211300Z - 221200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Organized severe thunderstorms are not currently forecast across the
contiguous United States through tonight.

...IL/IN...

Morning water-vapor imagery shows a subtle disturbance over the mid
MO Valley, which is forecast to quickly move southeast into the
southern Great Lakes by early evening. An associated surface trough
is forecast to develop from Lower MI into southern WI and northern
IL by late afternoon. Despite modest moisture (upper 40s to mid 50s
deg F surface dewpoints) returning northward into the Cornbelt, cold
mid-level temperatures (around -16 to -18 deg C at 500 mb) per
forecast soundings and heating will yield weak instability by
mid-late afternoon. Models continue to show isolated to scattered
storms late today into the evening. It remains uncertain whether a
couple of stronger cells will yield a threat of hail beyond a risk
for small hail. This activity will likely diminish by mid-late
evening as it moves southeast into central portions of IL/IN.

...Central CA...

Strong cyclonic flow associated with a mid-level low and associated
trough will move across central CA into the Great Basin during the
period. Cold temperatures aloft north of the midlevel jet will
support weak instability over parts of the central valleys. Given
early precipitation and clouds, as well as marginal low-level shear,
severe storms appear unlikely. However, a few strong storms may
occur late in the afternoon if sufficient heating occurs behind the
early day rain. Small hail appears most probable with the strongest cells.

..Smith/Thompson.. 04/21/2026

$$

--- ScorpioBBS/QWK v0.31a (Linux/x86_64)
* Origin: Project Scorpio TEST (618:250/6)

ACUS01 KWNS 301248
SWODY1
SPC AC 301246

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0746 AM CDT Thu Apr 30 2026

Valid 301300Z - 011200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
TEXAS AND COASTAL/SOUTHERN LOUISIANA...

...SUMMARY...
Thunderstorms with isolated large hail and gusty winds will be
possible mainly this evening and tonight across parts of southwest/south-central Texas towards the middle Texas Coast, and
this afternoon across coastal/southern Louisiana.

...Texas...

Strong westerly mid-flow will be maintained across the southern
Plains into the Southeast today, as a mid/upper-level low currently
off the coast of Baja California quickly moves eastward through the
period. A surface front is currently stalled across parts of south
TX, and most of the thunderstorms forecast to develop across TX
through tonight are expected to remain elevated. Ascent preceding
the shortwave trough should eventually encourage convection to
develop near the TX Big Bend late this evening, and spread eastward
towards the middle TX Coast through early Friday morning. Sufficient
MUCAPE and strong cloud-layer shear will support an isolated threat
for severe hail with any elevated supercells that can develop.
Strong to locally damaging winds may also occur as supercells
encounter greater instability across south-central to coastal TX
late tonight, even if they remain slightly elevated. Overall
confidence in coverage of severe convection remains too low to
include greater severe hail probabilities and a Slight Risk with
this update.

...Coastal/Southern Louisiana...

A convectively reinforced surface front is draped across
southern/coastal LA this morning, with thunderstorms ongoing to its
north. Greater instability will exist to the south of the front
across coastal LA this afternoon. Thunderstorms that develop/move
across the front later today could pose some risk for locally
damaging winds and marginally severe hail given weak to moderate
instability and strong deep-layer shear.

...Coastal South Carolina...

Thunderstorms capable of producing occasional strong/gusty winds
should move offshore within the next hour or two. The overall severe
wind threat appears too limited to include 5% probabilities.

..Gleason/Jewell.. 04/30/2026

$$

--- Scorpio BBS
* Origin: (618:250/6)

ACUS01 KWNS 131231
SWODY1
SPC AC 131230

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0730 AM CDT Mon Jul 13 2026

Valid 131300Z - 141200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE SOUTHEAST AND MONTANA...

...SUMMARY...
Thunderstorms with isolated strong to severe winds may occur this
afternoon and evening across parts of the Southeast and Montana.

...Southeast...
A very weak mid-level trough will persist over the Deep South and
Carolinas today, with modest westerly flow. Although rich low-level
moisture remains present across these areas, multiple days of
convective overturning has resulted in rather poor lapse rates
aloft. This, along with persistent cloudiness, should limit to some
degree how much instability will develop this afternoon with
filtered daytime heating. Deep-layer shear will also remain weak,
and thunderstorms should generally be disorganized. Some loose
clustering may eventually occur with convection spreading eastward
from the central Gulf Coast towards the FL Peninsula, where
low-level lapse rates should become steepened by peak afternoon
heating. Isolated damaging winds appear possible with the strongest
cores from parts of FL into eastern GA and SC ahead of the weak
mid-level trough.

...Montana...
Mid/upper-level ridging will extend from the southern/central
Rockies to the northern Plains/Upper Midwest through the period,
with a belt of enhanced southwesterly mid-level flow over
western/central MT. High-based thunderstorms may develop this
afternoon across parts of southwest into central MT amid a deeply
mixed boundary layer. While low-level moisture and related
instability are both expected to remain limited, some risk for
occasional strong to severe gusts may accompany this convection as
it spreads northward through the early evening before weakening.

...Arizona...
Showers and isolated thunderstorms are still ongoing this morning
across parts of southern AZ. While mid-level east-southeasterly flow
will persist today across much of AZ on the southern periphery of
prominent upper ridging, it remains unclear how much destabilization
will occur in the wake of this morning's convection. Whether
convection will be able to spread westward off the higher terrain of
southeast AZ and the Mogollon Rim is also uncertain. Have therefore
not included low severe wind probabilities with this update.

..Gleason/Thornton.. 07/13/2026

$$

--- Scorpio BBS
* Origin: capitolcityonlinet.net * KY, USA (618:250/10)

ACUS01 KWNS 151202
SWODY1
SPC AC 151200

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0700 AM CDT Wed Jul 15 2026

Valid 151300Z - 161200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE MID-ATLANTIC...NORTHERN NEW ENGLAND...NORTHERN ROCKIES/HIGH PLAINS...PACIFIC NORTHWEST...ARIZONA...AND SOUTH-CENTRAL TEXAS...

...SUMMARY...
There is a conditional risk for severe thunderstorms capable of
producing large hail and damaging winds across parts of the
Mid-Atlantic this afternoon and evening. Isolated damaging winds
appear possible for portions of northern New England, the northern
Rockies/High Plains, Pacific Northwest, and Arizona. A brief tornado
or two may also occur across parts of south-central Texas.

...Mid-Atlantic...
Hot temperatures are forecast south of a front that will be draped
across southern New England into the northern Mid-Atlantic by peak
afternoon heating. Coupled with dewpoints in the upper 60s to low
70s, this will contribute to a moderately unstable airmass, with
MLCAPE of 1500-2500 J/kg probable. The strongest mid-level height
falls/forcing for ascent associated with a shortwave trough over
Ontario/Quebec into New England are expected to remain generally
north of the surface front. Therefore, robust convective development along/south of the boundary in the northern Mid-Atlantic remains
highly uncertain. Another factor that could limit thunderstorm
initiation is the potential for more muted instability across the
warm sector due to smoke from upstream wildfires.

With continued uncertainty regarding initiation, have maintained the
Marginal Risk across the Mid-Atlantic with no changes. However, on
the condition that surface-based thunderstorms develop, the presence
of seasonably strong mid-level winds and resultant 40-50+ kt of
effective bulk shear would support supercells/multicells capable of
both severe hail and damaging winds.

...Northern New England...
Within the zone of strongest forcing for ascent associated with a
mid-level shortwave trough moving quickly eastward from southern
Ontario/Quebec into New England today, a band of low-topped showers
and thunderstorms may develop during the afternoon in a weakly
unstable environment. Steepening low-level lapse rates, a unidirectional/westerly wind profile with height through mid levels,
and 30-40 kt of flow around 1-2 km AGL will support the potential
for locally damaging wind gusts, assuming convection develops and
can become surface based.

...Northern Wyoming into Southern Montana...
A weak/embedded mid-level vorticity maximum evident on water vapor
satellite imagery over the northern Great Basin this morning will
move northeastward today across the northern Rockies and adjacent
High Plains. Diurnal heating across the higher terrain coupled with
the glancing influence of this subtle disturbance should foster the
development of scattered afternoon thunderstorms. Weak to moderate
instability is forecast, with a relatively deep and well-mixed
boundary layer across lower elevations. Recent guidance continues to
show some potential for upscale growth into a loosely organized
cluster with cold pool organization and a risk for isolated severe
wind gusts into the evening. However, the overall severe threat
should be tempered by modest deep-layer shear.

...Pacific Northwest...
Isolated to scatted thunderstorms should develop this afternoon
along and east of the Cascades from central OR into southern WA.
This convection will be aided by orogrpahic influences and modest
large-scale ascent preceding a closed upper low off the coast of the
Pacific Northwest. Recent NAM/RAP forecast soundings show a deeply
mixed boundary layer developing across this region through peak
afternoon heating, with weak MLCAPE present. Enhanced southwesterly
mid-level flow should support sufficient deep-layer shear for some
updraft organization, and isolated severe gusts may occur with the
stronger cores as they spread north-northeastward through the evening.

...Arizona...
Weak east-northeasterly mid-level flow is forecast today across AZ
on the southern periphery of upper ridging extending across much of
the central CONUS. Daytime heating of a seasonably moist low-level
airmass across southern/central AZ will yield weak to moderate
instability by mid afternoon with a very well-mixed boundary layer.
This environment should support isolated strong to severe gusts as
convection initially develops over the Mogollon Rim and higher
terrain of southeast AZ, before subsequently spreading westward into
the lower deserts. However, a more organized severe wind threat will
likely be limited by weak deep-layer shear.

...South-Central Texas...
A weak mid-level low over southwest TX this morning should make only
slow westward progress through the period across the southern High
Plains. Modest winds at low levels veer to southwesterly with height
at mid levels per recent VWPs from KDFX/KEWX. Up to 100 m2/s2 of 0-1
km SRH may be sufficient for some low-level rotation and perhaps a
brief tornado or two with ongoing convection given a very moist
low-level airmass. This threat may continue through the day as the
boundary layer gradually destabilizes with filtered daytime heating.

..Gleason.. 07/15/2026

$$

--- Scorpio BBS
* Origin: capitolcityonlinet.net * KY, USA (618:250/10)