148
ACUS01 KWNS 311632
SWODY1
SPC AC 311630

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1130 AM CDT Fri May 31 2024

Valid 311630Z - 011200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF
SOUTH-CENTRAL TEXAS INTO THE EDWARDS PLATEAU...THE ARK-LA-MISS...AND
PARTS OF THE CENTRAL AND SOUTHERN HIGH PLAINS...

...SUMMARY...
A few severe storms with large hail and damaging winds will be
possible this afternoon/evening across the central/southern High
Plains, from southwest Texas to the Texas coast, and across the
Ark-La-Miss.

...Synopsis...
Water-vapor imagery late this morning shows a mid- to upper-level
shortwave trough over the Red River and this feature is forecast to
move east to the Ark-La-Miss by early tonight.  An MCV was noted
over central MS this morning with likely another convectively
augmented circulation over the lower Sabine Valley.  Farther north,
broad cyclonic mid-level flow will remain centered over the Dakotas
and displaced with a residual frontal zone draped from MN
southwestward through NE and into the CO High Plains.

...Southern half of TX into the lower MS Valley...
Expansive MCS this morning over the TX coast will continue to push
southeast into the Gulf.  The northern extent of the MCS has moved
into southwest LA late this morning.  Visible-satellite imagery
shows a large cirrus canopy over the Arklatex.  The airmass will
become moderately unstable across southeast/eastern AR in areas void
of thicker cloud cover and to the northwest of a weakening MCV.  It
seems some rejuvenation of thunderstorms will occur on the leading
edge of outflow over LA and eventually farther north into AR later
this afternoon.  Strong to locally damaging gusts will be the
primary severe hazard with the more intense thunderstorms.

Farther southwest, a capped and destabilizing airmass to the south
of an outflow boundary from the earlier MCS, will become strongly
unstable as heating contributes to 2500-4000 J/kg MLCAPE from
south-central TX into the Trans-Pecos.  Long, straight-line
hodographs will favor supercells.  Main limiting factor will be
isolated storm coverage.  An attendant hail/wind risk will likely
accompany the stronger storms later this afternoon/evening.

...Central/Southern High Plains...
Not much change in thinking from the previous outlook update.  A
weak upslope regime will become established during the day, and
cloud breaks will allow pockets of surface heating (stronger farther
south toward southeast CO).  Potentially moderate buoyancy (MLCAPE
of 1000-1500 J/kg) and sufficiently long/straight hodographs will
support supercells capable of producing large hail, while severe
gusts will also be possible with any upscale growth into small
clusters.  A couple of storm clusters could persist into the
overnight hours into western KS and the TX Panhandle in response to
a weak low-level jet and associated warm advection.

..Smith/Guyer.. 05/31/2024

$$