Mesoscale Discussion 1046 NWS Storm Prediction Center Norman OK 0132 PM CDT Tue May 28 2024 Areas affected...portions of southwestern Texas Concerning...Severe potential...Watch likely Valid 281832Z - 282000Z Probability of Watch Issuance...80 percent SUMMARY...The severe threat should increase through the afternoon, with a possibly more rapid uptick in storm intensification for cells interacting with an outflow boundary. These storms will initially have a damaging gust/hail threat, though a tornado cannot be ruled out with storms interacting with the boundary. Convective trends are being monitored for the need of a WW issuance. DISCUSSION...Rapidly deepening CU have developed over the Trans Pecos region in Texas, atop a deep and well-mixed boundary layer. Based on the latest RAP forecast soundings, the boundary layer extends to somewhere between 600-500 mb, so convective initiation will result in high-based thunderstorms. Given the 9-10+ C/km low-level lapse rates in the boundary layer, any of the more intense storms that form could produce dry downbursts, and a dry microburst capable of 65+ kt gusts cannot be completely ruled out. As the storms progress eastward, they will move into an increasingly moister and more unstable airmass. At the same time, they will interact with a southwestward-moving outflow boundary generated by an earlier MCS. Enhanced lift along this boundary may support an uptick in thunderstorm intensity for any updrafts crossing this boundary. Elongated hodographs and 40+ kts of effective bulk shear suggest that multicells and splitting supercells will be the main modes of convection, with large hail possible. Some stones may exceed 2 inches in diameter. It is unclear precisely when an uptick in greater severe coverage will occur. Nonetheless, the CAPE/shear parameter space and synoptic environment suggest that an appreciable severe threat will unfold at some point this afternoon, when a WW issuance will ultimately be necessary. ..Squitieri/Hart.. 05/28/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...EWX...SJT...MAF... LAT...LON 31160420 31940359 32250235 31890110 31280067 30550068 30070102 30030226 30050313 30400407 31160420