Storm Prediction Center Mesoscale Discussion 405

   Mesoscale Discussion 0405
   NWS Storm Prediction Center Norman OK
   0757 PM CDT Tue Apr 09 2024

   Areas affected...Parts of south TX

   Concerning...Severe potential...Watch likely 

   Valid 100057Z - 100300Z

   Probability of Watch Issuance...95 percent

   SUMMARY...Severe storm development is expected later this evening.
   Large hail will be possible initially, with an increasing severe
   wind risk with time.

   DISCUSSION...The western portion of surface boundary is beginning to
   move southward as a cold front across parts of the southwest TX Hill
   Country this evening. Later this evening, this front will begin
   intercepting rich low-level moisture which is streaming westward
   across south-central TX. Increasing moisture beneath steep midlevel
   lapse rates will support MUCAPE increasing above 2000 J/kg near the
   front. As this occurs, increasing ascent ahead of a mid/upper-level
   trough over west TX will aid in storm development near and to the
   immediate cool side of the boundary.

   Strong mid-upper level southwesterly flow will support effective
   shear of greater than 50 kt region wide, and initial development may
   evolve quickly into supercells with a threat of very large hail.
   However, quick upscale growth will be possible, as convection moves
   into a region where rather strong heating and steepening of
   low-level lapse rates occurred earlier today, a scenario supported
   by recent HRRR and RRFS runs. Should this occur, an increasing
   threat for significant severe-wind gusts (possibly in the 70-85 mph
   range) could begin spreading east/northeastward later tonight. Watch
   issuance is likely by 03Z due to the increasing hail and severe-wind
   potential.

   ..Dean/Hart.. 04/10/2024

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

   ATTN...WFO...HGX...CRP...EWX...BRO...

   LAT...LON   28020041 29839871 29859764 29819654 29479637 29159619
               28659594 26889742 26689838 26649916 26729941 27079969
               28020041