US Mesoscale Discussions

Storm Prediction Center Mesoscale Discussion 1046

   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

   ..Squitieri/Hart.. 05/28/2024

   ...Please see for graphic product...


   LAT...LON   31160420 31940359 32250235 31890110 31280067 30550068
               30070102 30030226 30050313 30400407 31160420 

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