MD 2196 CONCERNING SEVERE POTENTIAL…WATCH UNLIKELY FOR PORTIONS OF SOUTHEAST/COASTAL TX
Mesoscale Discussion 2196
NWS Storm Prediction Center Norman OK
0236 PM CDT Mon Sep 25 2023
Areas affected…Portions of southeast/coastal TX
Concerning…Severe potential…Watch unlikely
Valid 251936Z – 252200Z
Probability of Watch Issuance…20 percent
SUMMARY…An isolated threat for strong to damaging winds should
exist with thunderstorms moving southward this afternoon. Watch
issuance appears unlikely.
DISCUSSION…Thunderstorms have gradually developed early this
afternoon across parts of southeast TX, along and near a stalled
surface front. Strong diurnal heating of a moist low-level airmass
is contributing to around 2000-2500 J/kg of MLCAPE per latest
mesoanalysis estimates. Mid-level west-northwesterly flow on the
eastern periphery of an upper ridge centered over the Rockies
remains modest based on recent VWPs from KHGX. Still, veering of the
wind profile with height through mid levels and modest strengthening
around 3-6 km AGL is supporting around 20-25 kt of effective bulk
shear. Current expectations are for the ongoing convection to
gradually move south-southeastward over the next few hours,
eventually approaching the Houston metro and vicinity. With
steepened low-level lapse rates present, occasional strong to
damaging downdraft winds up to 50-60 mph appear possible, especially
if convection can grow upscale into a loosely organized cluster.
Modest mid-level lapse rates and deep-layer shear should temper the
hail threat to some extent. But, isolated instances of marginally
severe hail up to about 1 inch in diameter may occur with the
strongest cores. The overall severe threat should be tempered by
weak low-level and deep-layer shear, with watch issuance unlikely.
..Gleason/Guyer.. 09/25/2023
…Please see www.spc.noaa.gov for graphic product…
ATTN…WFO…LCH…HGX…FWD…EWX…
LAT…LON 31039650 30929571 30989442 30739377 29849394 29669408
29479436 28869537 28919613 29549672 30309708 30809705
31039650
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