601
ACUS03 KWNS 221924
SWODY3
SPC AC 221923

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0223 PM CDT Thu May 22 2025

Valid 241200Z - 251200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
THE SOUTHERN PLAINS...

...SUMMARY...
Severe storms are likely across portions of the southern Plains on
Saturday. Severe wind gusts and large hail are the main threats, and
a few instances of 2+ inch diameter hail may occur. Isolated strong
to severe storms remain possible across a broad region from the
central High Plains to the Southeast.

...Synopsis...
A mid-level trough will continue to progress eastward across the
Interior West as upper ridging persists over the central CONUS, and
broad northwesterly mid-level flow (from a departing trough)
overspreads the Mid-MS Valley to the East Coast on Saturday.
Relatively rich low-level moisture will continue to pivot around a
quasi-stationary surface low over the southern High Plains, fueling
the potential for strong thunderstorm development from the High
Plains to the Southeast. Thunderstorms will be ongoing at the start
of the period over the central Plains into the Lower MS Valley. The
morning convection may leave an outflow boundary to serve as the
impetus for more robust, severe storm development Saturday afternoon
across far northwest TX into western and central OK.

...Far Northwest Texas into Western and central Oklahoma...
Mid-morning thunderstorms, perhaps in the form of an MCS, will be
traversing the terminus of a weakening low-level jet, leaving behind
an outflow boundary, likely positioned somewhere near the KS/OK
border. By afternoon, redevelopment of storms is likely ahead of the
surface low and along/south of the pre-existing boundary. The
airmass preceding these storms will be very to extremely unstable,
with low 70s F dewpoints beneath 9+ C/km mid-level lapse supporting
deep, wide CAPE profiles, with 4000-5000 J/kg MLCAPE values
expected. Modest veering with height will support 35 kts of
effective bulk shear, characterized by hodographs with some
elongation and curvature. Given the expected degree of instability,
supercells are the likely storm mode, with severe wind and large to
very large hail the main threats.

...Portions of Western Texas...
Strong heating of the boundary layer will encourage the eastward
advancement of the dryline, which will support thunderstorm
initiation by mid to late afternoon. These storms should be
high-based as they develop atop a boundary layer that may extend up
to at least 700 mb, with 30+ F T/Td spreads likely. Deep-layer flow
and shear will be weaker farther south, and when considering the
high degree of evaporative cooling expected in a dry boundary layer,
outflow-dominant multicells are expected. An instance of severe hail
may occur with initial updrafts, followed by severe gust potential
with subsequent downbursts and larger scale outflow from decaying
multicells.

...Central High Plains...
Surface-850 mb upslope flow along the higher terrain of the central
High Plains may encourage isolated thunderstorm development by mid
to late afternoon. NAM forecast soundings show a stable boundary
layer in place, suggesting that storms should be elevated.
Nonetheless, forecast hodographs show considerable elongation above
the stable layer, indicating that multicell and supercell structures
are possible, perhaps accompanied by a sparse hail/strong gust
threat.

...Lower MS Valley into the Southeast...
The aforementioned strong storms/possible MCS across the southern
Plains during the morning hours may shift eastward along a diffuse
baroclinic boundary. Assuming these storms persist toward the
Southeast with some appreciable degree of intensity, an instance or
two of strong wind gusts or hail are possible. Later Saturday
evening/overnight, strong storms across the southern Plains may
persist eastward as the low-level jet strengthens. Should this be
the case, 7-8 C/km mid-level lapse rates (supporting over 2000 J/kg
MLCAPE), along with elongated hodographs, may support the approach
of another nocturnal MCS, accompanied by a sparse wind/hail threat.

..Squitieri.. 05/22/2025

$$