459
ACUS02 KWNS 260622
SWODY2
SPC AC 260620

Day 2 Convective Outlook CORR 1
NWS Storm Prediction Center Norman OK
0120 AM CDT Sun May 26 2024

Valid 271200Z - 281200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS MONDAY INTO MONDAY
NIGHT ACROSS PARTS OF EASTERN WEST VIRGINIA...SOUTHERN
PENNSYLVANIA...MUCH OF VIRGINIA AND MARYLAND...NORTHERN NORTH
CAROLINA...DELAWARE AND SOUTHERN NEW JERSEY...AS WELL AS ACROSS MUCH
OF WESTERN GEORGIA...ALABAMA...CENTRAL AND SOUTHERN MISSISSIPPI AND
EASTERN LOUISIANA...

CORRECTED FOR WIND PROBABILITY GRAPHIC

...SUMMARY...
Severe thunderstorms are possible across parts of the Mid Atlantic
and the Gulf Coast states Monday into Monday night, with severe wind
and hail the primary potential hazards.

...Synopsis...
Mid/upper flow still appears likely to undergo amplification across
the northern mid-latitudes of the Pacific and western North America
into and through the Memorial Day Holiday.  This is forecast to
include digging troughing offshore of the Pacific Northwest coast,
to the south of a broad low developing across the northeastern
Pacific, and building downstream ridging across the northern U.S.
Rockies and Canadian Prairies.

Farther downstream, several short wave perturbations are forecast to
consolidate into more prominent larger-scale troughing across the
mid/upper Mississippi Valley into the northern and middle Atlantic
Seaboard.  One of the more prominent perturbations appears likely to
turn northeast of the Lake Huron/Georgian Bay vicinity during the
day, accompanied by a relative compact, but deep, surface cyclone.
In its wake, a remnant plume of elevated mixed-layer air likely will
become increasing suppressed across the Southeast and lower
Mississippi Valley, while a surface cold front advances into and
across the Appalachians.

Preceding the front, surface troughing is forecast to deepen to the
east of the Blue Ridge during the day, beneath increasingly difluent
and divergent upper flow, downstream of a short wave trough pivoting
east-northeast of the lower Ohio Valley.

...Mid Atlantic..
Latest model output appears a bit weaker than prior guidance with
regard to the wave emerging from the lower Ohio Valley, and a little
more unclear concerning more subtle, perhaps convectively generated,
perturbations preceding this wave.  However, a seasonably moist
boundary layer to the east of the deepening lee surface troughing is
still forecast to become characterized by sizable CAPE as 40-50+ kt
west-southwesterly mid-level flow noses northeast of the southern
Appalachians.  This is expected to contribute to an environment
potentially conducive to organized thunderstorm development,
including supercell structures.  It still appears possible that
consolidating pre-cold frontal convection across and east of the
Allegheny Mountains could intensify and organize further to the east
of the Blue Ridge by late afternoon, accompanied by potentially more
widespread strong to severe wind gusts into Monday evening.

...Gulf States...
Beneath a remnant plume of relatively steep lower/mid-tropospheric
lapse rates, seasonably high boundary-layer moisture content is
forecast to contribute to large CAPE on the order of 2000-4000+ J/kg
by late Monday afternoon, along a corridor across the lower
Mississippi Valley into the southern Appalachians.  Beneath modest,
broadly cyclonic mid-level flow, the initiation of vigorous
thunderstorm development appears probable by late Monday afternoon.
The latest NAM, in particular, is suggestive that upscale growth may
contribute to a substantive surface cold pool and rear-inflow which
may be accompanied by increasingly widespread strong to severe
surface gusts across Alabama and adjacent portions of western
Georgia, central and southern Mississippi.  It is possible severe
probabilities may need to be increased further across this region in
later outlooks, as model spread decreases.

..Kerr.. 05/26/2024

$$