566
ACUS01 KWNS 040538
SWODY1
SPC AC 040536

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1236 AM CDT Sat May 04 2024

Valid 041200Z - 051200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE SOUTHERN HIGH PLAINS INTO THE EDWARDS PLATEAU...

...SUMMARY...
Scattered severe thunderstorms are expected across parts of the
southern High Plains into the Hill Country of central Texas this
afternoon and evening. Several storms may produce very large hail,
and a couple strong tornadoes are possible.

...Southern High Plains to the Hill Country of TX...

Water-vapor imagery depicts a low-amplitude short-wave trough off
the Baja Peninsula. This feature will advance across northern Mexico
by early evening as a 500mb speed max translates toward the Big Bend
of west TX, subsequently moving into central TX by 05/12z. A
reservoir of very moist/unstable air will reside across south
TX/Edwards Plateau into portions of west TX. Robust convection will
easily develop ahead of the short wave and quickly become severe
during the afternoon. Very large hail and the threat for tornadoes
can reasonably be expected.

Early this morning, surface pressures are building across the
central Plains in the wake of ejecting northern-stream short-wave
trough. Surface front will surge across the TX South Plains early in
the period, and will likely arc along/near I-20 into southeast NM by
18z. Latest model guidance suggests strong boundary-layer heating
will occur ahead of the wind shift across far west TX into the Trans
Pecos. Forecast soundings, south of the front, suggest surface
parcels will reach their convective temperatures by 20z, just east
of the dryline. This feature will be forced deep into west TX and
will be one of the foci for convective development, along with the
cold front. Latest NAM PFC for INK at 20z exhibits MLCAPE on the
order of 3500 J/kg with surface-6km bulk shear around 45kt.
Scattered supercells will likely develop by mid afternoon and
quickly attain severe levels. This activity will grow upscale and
shift downstream, aided by the progressive short wave. In response
to the short wave, LLJ is forecast to focus across west TX through
early evening then strengthen and shift east toward the I-35
corridor by sunrise Sunday. Initial convective mode will be
supercellular and very large hail can be expected. Additionally,
moistening boundary layer will support tornadoes, possibly strong,
as shear will be strong. With time, MCS is expected to mature and
propagate toward central TX during the overnight hours.

..Darrow/Wendt.. 05/04/2024

$$