ZCZC SPCSWOMCD ALL ACUS11 KWNS 072152 SPC MCD 072152 TXZ000-080015- Mesoscale Discussion 0715 NWS Storm Prediction Center Norman OK 0452 PM CDT Sun May 07 2023 Areas affected...Rio Grande Valley Concerning...Severe potential...Watch possible Valid 072152Z - 080015Z Probability of Watch Issuance...40 percent SUMMARY...Currently monitoring convective trends across the Rio Grande Valley for the possibility of isolated severe thunderstorms capable of large hail and severe gusts. DISCUSSION...Visible satellite imagery shows a couple of clusters of thunderstorms over northern Mexico west of Del Rio and southwest of Laredo on the higher terrain. A stout elevated mixed layer was observed on the Del Rio 12 UTC raob. The associated warm layer/capping inversion located near 875 mb will likely inhibit or greatly limit surface-based development over south-central and Deep South TX this afternoon. Nonetheless, strong heating has yielded temperatures ranging from the mid 80s to the mid 90s across the Rio Grande Valley. Moist low levels (mid 60s to lower 70s deg F surface dewpoints) are contributing to a very unstable airmass (2500-4000 J/kg MLCAPE). A belt of strong high-level flow will continue to reside across northern Mexico and TX this evening. In the absence of appreciably strong forcing for ascent, considerable uncertainty remains whether a few thunderstorms will develop on the aggregate outflow from storms in Mexico west and southwest of Laredo, or storms west of the Del Rio eventually coalesce and move east into TX in the southern part of the Edwards Plateau early this evening. If storms manage to develop east across the Rio Grande (most likely near Del Rio), a risk for large hail and severe gusts will probably accompany the storms for a few hours before eventually dissipating by mid evening. ..Smith/Guyer.. 05/07/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...CRP...EWX...BRO... LAT...LON 29610178 30190104 30270048 29109954 27689892 26539905 26499933 29610178 NNNN