411
ACUS01 KWNS 200525
SWODY1
SPC AC 200524

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1224 AM CDT Sat Jul 20 2024

Valid 201200Z - 211200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE
CENTRAL/SOUTHERN HIGH PLAINS AND THE SOUTHEAST...

...SUMMARY...
Strong to isolated severe thunderstorms are possible over parts of
the Southeast and central to southern High Plains, mainly from
mid-afternoon to evening.

...Central to southern High Plains...
A moderate mid-level northwesterly flow regime will persist between
an anticyclone over the Great Basin and a low-amplitude trough from
the Great Lakes towards the Ozarks. The latter part of this minor
trough may be augmented by a southeast-moving MCV from remnants of
weakening convection currently over western KS. Scattered to
numerous thunderstorms are expected during the afternoon over the
central to southern Rockies, spreading across the adjacent High
Plains. An additional corridor of scattered thunderstorms may be
focused over northwest TX into southwest OK, where differential
boundary-layer heating should be more pronounced to the
south-southwest of early-day convection/cloud cover.

After fairly extensive convection on Friday evening, instability
will be comparatively weaker this afternoon. Still, with a moderate
combination of buoyancy, characterized by MLCAPE of 1000-2000 J/kg,
and deep-layer shear, a few clusters and transient supercells may
develop across the region. Cooler-than-normal surface temperatures
north of northwest TX suggest the wind threat may be more strong
than severe, a signal supported by 00Z HREF guidance. Isolated
severe hail may be the primary hazard over the central High Plains.

...Southeast...
Between a low-amplitude mid-level trough from the Great Lakes to the
Ozarks and the subtropical ridge in the western Atlantic, a belt of
modestly enhanced southwesterly 700-500 mb winds should exist across
parts of the Southeast from eastern GA to southern VA. Scattered
thunderstorms appear most probable during the afternoon in parts of
AL/GA/north FL, and separately in the lee of the southern
Appalachians to the VA/NC border. Destabilization within the
enhanced flow regime should be more pronounced between these regimes
over the Carolina Piedmont and coastal plain. Upstream convection
may consolidate into loosely organized multicell clusters capable of
producing sporadic strong gusts and localized tree damage.

..Grams/Lyons.. 07/20/2024

$$