MESOSCALE DISCUSSION 0447
   NWS STORM PREDICTION CENTER NORMAN OK
   0248 AM CDT SAT APR 25 2015

   AREAS AFFECTED...TX MIDDLE RIO GRANDE VALLEY/SOUTH-CENTRAL TX

   CONCERNING...SEVERE POTENTIAL...WATCH LIKELY 

   VALID 250748Z - 250915Z

   PROBABILITY OF WATCH ISSUANCE...80 PERCENT

   SUMMARY...AT LEAST ISOLATED SEVERE THUNDERSTORMS MAY CONTINUE TO
   INCREASE/DEVELOP GENERALLY EASTWARD OVERNIGHT ACROSS PORTIONS OF
   SOUTH-CENTRAL TX...WITH SEVERE HAIL AS THE PRIMARY RISK.

   DISCUSSION...STORMS HAVE RECENTLY INCREASED ACROSS SOUTH-CENTRAL
   TX...GENERALLY BETWEEN THE DEL RIO/SAN ANTONIO VICINITIES AS OF
   0730Z/230AM CDT. THIS DEVELOPMENT IS OCCURRING WITHIN A
   MOIST/MODERATELY UNSTABLE ENVIRONMENT NEAR A RESIDUAL
   BOUNDARY...WITH THE 00Z DEL RIO OBSERVED SOUNDING PREVIOUSLY
   SAMPLING 2600+ MLCAPE AND A 15 G/KG MEAN MIXING RATIO WITH 1.55 INCH
   PRECIPITABLE WATER. GIVEN THIS RESERVOIR OF
   MOISTURE/INSTABILITY...VERY STRONG/LARGELY UNIDIRECTIONAL SHEAR
   THROUGH THE CLOUD-BEARING LAYER WILL SUPPORT SPLITTING STORMS/SOME
   SUPERCELLS WITH LARGE HAIL AS THE PRIMARY HAZARD.

   ..GUYER/CORFIDI.. 04/25/2015


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

   LAT...LON   29240055 29800016 30209896 29989719 29409654 28689686
               28329813 28850014 29240055