ACUS01 KWNS 050101
SWODY1
SPC AC 050059

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0759 PM CDT Sun May 04 2025

Valid 050100Z - 051200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE UPPER OHIO RIVER VALLEY...PARTS OF THE MID-ATLANTIC...AND
SOUTHEAST NEW MEXICO AND FAR WESTERN TEXAS....

...SUMMARY...
Isolated to scattered severe thunderstorms will remain possible
through the late evening hours across parts of southeast New Mexico
and western Texas as well as across parts of the central
Appalachians and parts of the Carolinas and southeast Virginia.

...Synopsis...
An omega blocking pattern will continue to become established aloft
across the country as a pair of upper lows linger over the OH River
Valley and Southwest. Broad scale ascent ahead of both of these low
will continue to promote thunderstorm chances across the eastern
U.S. and the Intermountain West through early Monday morning.

...Upper Ohio River Valley...
As of 00 UTC, a lobe of mid-level vorticity pivoting into the upper
OH River Valley, coupled with weak mid-level warm advection,
continues to promote widely scattered strong/severe thunderstorms. A
recent 00 UTC sounding from Pittsburg, PA sampled limited
mixed-layer buoyancy, but recent high-res guidance and mesoanalysis
estimates suggests a corridor of somewhat higher buoyancy (500-750
J/kg MLCAPE) resides from northern WV into western PA. Additionally,
30-40 knot mid-level flow sampled by the recent RAOB is adequate to
support supercells. The thermodynamic environment should continue to
wane heading into the overnight hours, and stronger forcing for
ascent will increasingly overspread a less buoyant air mass to the
north, though a severe hail threat may persist for the next couple
of hours.

...Coastal Carolinas into southeast Virginia...
Thunderstorms continue to develop and propagate along a weakly
confluent marine boundary draped from south-central VA into the
eastern Carolinas. Dewpoints in the mid to upper 60s continue to
contribute to around 1000 J/kg MLCAPE (perhaps best sampled by the
00 UTC CHS sounding). A localized hail/wind threat should persist
with ongoing convection given adequate buoyancy and deep-layer
shear, but nocturnal cooling should increase low-level stability and
limit thunderstorm coverage and intensity through the overnight
hours. Latest guidance hints that an early-morning (10-12 UTC) round
of thunderstorms is possible across north-central NC into southeast
VA. Strong mid-level flow should remain over the region and may
support organized cells with an attendant hail/wind threat.

...New Mexico into western Texas...
Long-lived supercells continue to migrate across far southeast NM
into western TX as of 00 UTC. A strengthening low-level jet will
help elongate low to mid-level hodographs as well as maintain
moisture advection from the southeast. As a result, supercell
maintenance is likely for the next few hours before cells drift
further east into TX and out of the primary low-level jet/moist
advection axis. Persistent lift across the region in the vicinity of
the terminus of the low-level jet and within the left-exit region of
an approaching upper jet may support additional strong/severe storms
later tonight. However, more limited buoyancy/increased inhibition
should limit storm coverage. Therefore, opted to remove Slight-risk
caliber risk probabilities, but maintain low-end probabilities to
address the severe potential for additional overnight storms.

..Moore.. 05/05/2025

$$



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