MESOSCALE DISCUSSION 0782
   NWS STORM PREDICTION CENTER NORMAN OK
   0800 PM CDT FRI MAY 13 2011
   
   AREAS AFFECTED...PORTIONS OF THE NC-SC PIEDMONT
   
   CONCERNING...SEVERE THUNDERSTORM WATCH 299...
   
   VALID 140100Z - 140130Z
   
   THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 299
   CONTINUES.
   
   THERE IS A DECREASING STRONG AND PERHAPS ISOLD SEVERE RISK THE NEXT
   FEW HOURS.  A NEW WW WILL NOT BE REQUIRED AT THE 03Z EXPIRATION TIME
   AND AN EXTENSION-IN-TIME WILL LIKELY NOT BE NECESSARY.
   
   RADAR MOSAIC SHOWS PULSATING NATURE TO UPDRAFTS ALONG N-S ORIENTED
   WEAKENING CONVECTIVE COLD POOL MOVING SLOWLY EWD ACROSS THE I-77
   CORRIDOR IN NC.  SURFACE ANALYSIS DEPICTS A WEDGE OF COOLER AIR
   ALONG AND N OF A RESIDUAL DIFFERENTIAL HEATING BOUNDARY
   /CHARACTERIZED BY TEMPS IN THE UPPER 60S TO LOWER 70S/ EXTENDING
   FROM 20 WSW RDU TO 20 W GSO.  TO THE IMMEDIATE E OF THE SLOWLY
   MOVING COOL POOL...A HIGHER LOW LEVEL THETA-E PLUME IS BEGINNING TO
   BE PINCHED ON THE NRN END OVER S-CNTRL VA AND PARTS OF THE NC
   PIEDMONT TO THE W OF WHERE LOW CLOUDS IMPEDED MORE APPRECIABLE
   SURFACE-BASED DESTABILIZATION DURING THE DAY.  00Z GSO RAOB SHOWS
   WEAK WLY FLOW THROUGH THE TROPOSPHERE--WHICH WILL LIMIT STORM
   INTENSITY CONCURRENT WITH DIURNAL BOUNDARY LAYER STABILIZATION. 
   ALTHOUGH AN ISOLD STRONG/DMGG GUST OR TWO CANNOT BE RULED OUT FOR
   THE NEXT HOUR OR TWO...THE SEVERE RISK WILL CONTINUE TO DIMINISH
   WITH TIME.
   
   ..SMITH.. 05/14/2011
   
   
   ATTN...WFO...RAH...ILM...RNK...CAE...GSP...
   
   LAT...LON   34388161 35428124 35988076 36528023 36397970 36027910
               35697905 35197945 34667998 34498083 34388161