MESOSCALE DISCUSSION 0188
   NWS STORM PREDICTION CENTER NORMAN OK
   1053 AM CST THU FEB 21 2013
   
   AREAS AFFECTED...SERN TX
   
   CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 
   
   VALID 211653Z - 211830Z
   
   PROBABILITY OF WATCH ISSUANCE...40 PERCENT
   
   SUMMARY...MONITORING BAND OF PRE-FRONTAL SHOWERS AND ISOLATED TSTMS
   FOR POTENTIAL GROWTH INTO DISCRETE CONVECTION THAT MAY WARRANT A
   TORNADO WATCH ISSUANCE BY MIDDAY.
   
   DISCUSSION...16Z SURFACE ANALYSIS PLACED A CYCLONE AROUND 45 SE CRS
   WITH A WARM FRONT ARCING SEWD TO NEAR BPT AND A COLD FRONT EXTENDING
   SWWD TO CLL. PERSISTENT WARM SECTOR BAND OF SHOWERS/ISOLATED TSTMS
   HAS SHOWN SOME SIGNS OF DEEPENING AND SEPARATING INTO MORE DISCRETE
   CONVECTION IN THE PAST HALF HOUR AS THE SPATIAL GAP BETWEEN THIS AND
   THE COLD FRONT HAS DECREASED. IF THIS TREND CONTINUES...THERE IS
   CONCERN THAT A SUPERCELL OR TWO COULD FORM BEFORE CROSSING THE WARM
   FRONT AND BECOME INCREASINGLY ELEVATED ABOVE A COLDER/STABLE
   BOUNDARY LAYER. GIVEN 0-1 KM SRH AROUND 500 M2/S2 SAMPLED IN THE HGX
   VWP...A TORNADO AND LOCALLY DAMAGING WINDS WOULD BE THE PRIMARY
   THREATS IN THE WARM SECTOR...WITH A MARGINAL RISK FOR SEVERE HAIL N
   OF THE FRONT.
   
   ..GRAMS/HART.. 02/21/2013
   
   
   ATTN...WFO...LCH...SHV...HGX...
   
   LAT...LON   31239501 31319457 31129399 30549357 30069347 29749372
               29509445 29499491 29679522 29949551 30209567 30649551
               31239501