Storm Prediction Center Mesoscale Discussion 727

   Mesoscale Discussion 0727
   NWS Storm Prediction Center Norman OK
   0706 PM CDT Tue May 06 2025

   Areas affected...Far south Texas

   Concerning...Severe potential...Watch possible 

   Valid 070006Z - 070200Z

   Probability of Watch Issuance...40 percent

   SUMMARY...Thunderstorms developing west of the lower Rio Grande may
   cross into far south Texas later this evening. If this occurs, the
   environment is favorable for robust supercells with an attendant
   large hail and severe wind threat.

   DISCUSSION...Multiple attempts at sustained deep convection are
   underway along the eastern slopes of the Sierra Madre mountains to
   the west of the lower Rio Grande. Storms that can remain sustained
   away from the orographic ascent along the terrain will migrate into
   an increasingly moist/buoyant air mass with eastward extent into
   Deep South TX where they will likely intensify into robust
   supercells given a very buoyant and strongly sheared environment
   (MLCAPE values upwards of 4000 J/kg with ~60 knots of effective deep
   layer shear). One deeper/stronger cell northwest of Rio Grande City,
   TX has recently exhibited echo tops above 50 kft, suggesting that
   this cell could remain sustained for the next few hours and pose a
   downstream threat for large hail (potentially upwards of 2.0 to 3.5
   inches) and severe winds. Recent high-res guidance suggests multiple
   rounds of isolated convection may move into the region through the
   late evening and overnight hours.

   ..Moore/Smith.. 05/07/2025

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

   ATTN...WFO...CRP...BRO...

   LAT...LON   26349909 26589923 27119958 27289946 27269910 26969768
               26869740 26629735 26319722 25999722 25899727 25839749
               25949778 26039825 26109847 26199874 26269899 26349909 

   MOST PROBABLE PEAK WIND GUST...55-70 MPH
   MOST PROBABLE PEAK HAIL SIZE...2.00-3.50 IN