872
ACUS02 KWNS 171731
SWODY2
SPC AC 171729

Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1229 PM CDT Wed Jul 17 2024

Valid 181200Z - 191200Z

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

...SUMMARY...
Isolated strong to severe thunderstorms are possible Thursday
afternoon across the central and southern High Plains as well as
from the Virginia Tidewater across the eastern Carolinas.

...Synopsis...
An expansive upper-level ridge will be present across much of the
West into the Plains on Thursday. An upper trough will depart the
Northeast by the late afternoon/evening. A shortwave trough will
slide over the upper ridge in the northern Rockies. An MCV will
likely track eastward from the ArkLaMiss into Alabama. At the
surface, a cold front will be situated from the Mid-Atlantic into
the western Carolinas with a westward extension into the Mid-South
and southern Plains. This front will be more diffuse with westward
extent. Surface high pressure will be the predominant feature in the
Midwest and Ohio Valley with a weak surface low developing in
Montana ahead of the shortwave trough.

...Southeast Virginia into parts of the Carolinas...
Scattered to numerous storms are expected to develop along the cold
front by the afternoon. There is some uncertainty as to the degree
of destabilization that will occur. This is in part due to some
potential convection developing along the sea breeze with
outflow/cloud debris affecting storms that develop farther west
along the front. The airmass will be quite moist, however, and even
broken cloud cover will support 2000-3000 J/kg MLCAPE (larger values
being more probable with southern extent). With modest mid-level
flow along the southern periphery of the upper trough, effective
shear of 30-40 kts will support primarily multicells/linear clusters
with a few marginal supercells. Mid-level lapse rates will be weak
making large hail potential low. The primary hazard will be damaging
winds. Depending on the degree of destabilization, there could be
potential for a corridor of greater damaging wind potential should a
more organized cluster develop.

...Central/southern High Plains...
Very modest moisture return is expected to occur along the western
flank of the surface high. Forcing for ascent will be weak, but
widely scattered to possibly scattered convection will develop along
the terrain and within the weak lee trough. Storm coverage with
eastern extent is less certain, but outflow boundaries may provide a
focus for development. There will be some enhanced mid-level winds
across the region promoting 30-40 kts of effective shear. Moisture
is a bit uncertain, with some guidance showing dewpoints mixing into
the mid/upper 40s to perhaps low 50s F, but a few isolated cells and
multicell clusters could produce severe winds and large hail.

...Northwest/north-central Montana...
The shortwave trough will be weakening with time, but will be
well-timed with afternoon heating. Storms are possible within the
terrain and within a weak surface trough. The main uncertainty will
be low-level moisture. A storm or two could produce a strong wind
gust and small hail, but confidence is too low for unconditional
severe probabilities.

..Wendt.. 07/17/2024

$$