383
ACUS11 KWNS 051703
SWOMCD
SPC MCD 051702
TXZ000-051900-

Mesoscale Discussion 0639
NWS Storm Prediction Center Norman OK
1202 PM CDT Sun May 05 2024

Areas affected...South-central TX

Concerning...Severe potential...Watch possible

Valid 051702Z - 051900Z

Probability of Watch Issuance...60 percent

SUMMARY...Ongoing convection should intensify across parts of
south-central Texas at some point this afternoon. Primary threat
should be from large hail between 1.5 to 2.5 inches in diameter.
Localized severe wind gusts and a brief tornado will also be
possible. Timing of severe storms beyond isolated coverage is
somewhat uncertain.

DISCUSSION...Ongoing convection exists from Maverick to Fayette
counties in south-central TX and separately along the Middle TX
coast. Ascent tied to a low-amplitude shortwave impulse that is
moving northeast and recently crossed the Rio Grande will be
maximized over the next few hours. Sufficient cloud breaks have
yielded temperatures generally in the low to mid 80s within the very
richly moist boundary layer ahead of the ongoing storms. This will
support a continued plume of moderate buoyancy with MLCAPE of
1500-2500 J/kg, despite mid-level warming being well-progged to
occur in the wake of the shortwave impulse as it moves across the
area. Pronounced veering of the low-level wind profile with height
will also compensate for modest lower-level speeds and should
support at least transient supercell structures, with a primary
hazard of isolated large hail. Given the buoyancy profile, a
supercell or two may be longer-lasting, albeit slow-moving to the
southeast, as seemingly simulated by late morning HRRR and 12Z
NSSL-MPAS guidance. The less-than-ideal timing of large-scale ascent
does render uncertainty over the degree of severe storm coverage, as
well as longevity, especially towards early evening.

..Grams/Smith.. 05/05/2024

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...HGX...CRP...EWX...

LAT...LON   29099911 29589773 29669703 29169629 28759612 28359650
            28019716 27849790 27799917 28049979 28610028 29099911