MESOSCALE DISCUSSION 0816
   NWS STORM PREDICTION CENTER NORMAN OK
   0553 PM CDT WED MAY 13 2009
   
   AREAS AFFECTED...PORTIONS OF THE LOW ROLLING PLAINS/BIG COUNTRY OF
   TX
   
   CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 
   
   VALID 132253Z - 140000Z
   
   AN ISOLATED/CONDITIONAL SEVERE THREAT WILL EXIST ALONG SURFACE
   DRYLINE ACROSS PORTIONS OF THE LOW ROLLING PLAINS/BIG COUNTRY OF TX.
   IF A TSTM CAN BE SUSTAINED...VERY STEEP LOW/MID-LEVEL LAPSE RATES
   WOULD PROMOTE POTENTIAL FOR LARGE HAIL AND MICROBURSTS.
   HOWEVER...MODEST DEEP-LAYER SHEAR AND EXPECTED ISOLATED CONVECTIVE
   COVERAGE SHOULD PRECLUDE THE NEED FOR A WW ISSUANCE.
   
   22Z SUBJECTIVE SURFACE ANALYSIS PLACED A DRYLINE/COLD FRONT
   INTERSECTION INVOF W-CNTRL OK/ERN TX PANHANDLE BORDER...WITH THE
   DRYLINE EXTENDING SWD TO HASKELL COUNTY TX SWWD TO TERRELL COUNTY
   TX. TCU/SMALL CBS ARE EVIDENT ALONG THE DRYLINE IN KNOX/HASKELL
   COUNTIES. ALTHOUGH LATEST NAM/GFS/RUC GUIDANCE DO NOT PRODUCE ANY
   QPF ACROSS THIS REGION INTO THE EARLY EVENING...12Z HI-RES WRF-NMM
   DOES INDICATE ISOLATED CONVECTION MAY DEVELOP. ALTHOUGH LARGE-SCALE
   ASCENT APPEARS NEGLIGIBLE...MODIFIED 18Z OUN RAOB/RUC FORECAST
   SOUNDINGS SUGGEST THE AREA IS UNCAPPED TO MIXED-LAYER PARCELS. VERY
   STEEP LOW/MID-LEVEL LAPSE RATES SHOULD COMPENSATE FOR A WEAK
   DEEP-LAYER KINEMATIC PROFILE /PER JAYTON TX PROFILER/...AND MAY AID
   IN THE PRODUCTION OF A FEW SEVERE HAIL/WIND GUSTS.
   
   ..GRAMS.. 05/13/2009
   
   
   ATTN...WFO...FWD...OUN...SJT...LUB...
   
   LAT...LON   34259981 34289777 33719775 32819790 31869857 31619915
               31649966 31840028 32080054 32830011 34259981