Storm Prediction Center Mesoscale Discussion 923

   Mesoscale Discussion 0923
   NWS Storm Prediction Center Norman OK
   0507 PM CDT Sun May 31 2026

   Areas affected...Southwest Texas

   Concerning...Severe potential...Watch unlikely 

   Valid 312207Z - 010000Z

   Probability of Watch Issuance...20 percent

   SUMMARY...Marginally severe thunderstorms will be possible this
   afternoon across portions of southwest Texas. The most likely hazard
   will be strong gusty outflow winds with collapsing updrafts, but a
   few large hail reports may be possible with the strongest updrafts.
   A watch is not expected.

   DISCUSSION...Strong diurnal heating and weak large-scale ascent from
   a subtle low-latitude short-wave trough have combined to support
   thunderstorm development this afternoon across portions of southwest
   Texas. The thermodynamic environment across the area is
   characterized by MUCAPE values between 1000-2000 J/kg, with most
   storms developing near the higher MUCAPE values across the eastern
   portion of the highlighted area. Kinematically speaking, the overall
   environment is rather unfavorable for organized, sustained severe
   thunderstorms, with deep-layer shear generally less than 25 knots. 

   Given storm development within an environment an uncapped
   environment with MUCAPE values approaching 2000 J/kg and steep low-
   and mid-level lapse rates, marginally severe thunderstorms are
   possible this afternoon. The degree of instability and
   steep-mid-level lapse rates suggests the potential for marginally
   severe hail with the strongest updraft cores, and the steep
   low-level lapse rates should support strong thunderstorm outflows,
   especially with any collapsing core. 

   The overall severe threat should remain fairly isolated, thus a
   watch is not anticipated.

   ..Marsh/Guyer.. 05/31/2026

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

   ATTN...WFO...EWX...SJT...MAF...

   LAT...LON   29370422 31050430 31620404 32120372 32320296 32140216
               31690148 31390131 29730193 29750227 29640258 29200284
               28900306 28910333 29180393 29370422 

   MOST PROBABLE PEAK WIND GUST...55-70 MPH
   MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN