MESOSCALE DISCUSSION 1579
   NWS STORM PREDICTION CENTER NORMAN OK
   0132 AM CDT WED JUL 25 2012
   
   AREAS AFFECTED...EXTREME SWRN VA/EXTREME NERN TN/PARTS OF WRN NC
   
   CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 
   
   VALID 250632Z - 250730Z
   
   PROBABILITY OF WATCH ISSUANCE...20 PERCENT
   
   SUMMARY...A SMALL MCS THAT FORMED OVER EXTREME SERN KY INTO EXTREME
   SWRN VA HAS PRODUCED A COLD POOL AIDING IN AN INCREASE IN SEWD
   MOVEMENT /NEAR 40 KT/.  LOCALLY STRONG WIND GUSTS WILL BE POSSIBLE
   AS THIS ACTIVITY TRACKS SEWD THROUGH EXTREME SWRN VA/EXTREME NERN TN
   INTO WRN NC DURING THE NEXT FEW HOURS /UNTIL 08-09Z/.  GIVEN
   SPATIOTEMPORAL LIMITATIONS...A WW IS UNLIKELY AT THIS TIME.  AS
   STORMS CONTINUE TO FORM OVER ERN KY WITH A TENDENCY TO TRAIN
   SEWD...RAINFALL RATES OF 1.5-2 INCH PER HOUR ARE LIKELY...GIVEN A
   RICHLY MOIST AIR MASS.
   
   DISCUSSION...TRENDS IN REGIONAL RADAR IMAGERY INDICATED A SMALL MCS
   THAT FORMED OVER EXTREME ERN/SERN KY INTO EXTREME SWRN VA BETWEEN
   04-0530Z/ HAD PRODUCED HEAVY RAINFALL RATES /1-2+ IN/HR AS INDICATED
   BY RADAR ESTIMATES AND NESDIS SATELLITE ESTIMATES FOR BUCHANAN
   COUNTY VA/.  ADDITIONAL STORMS HAVE BEGUN TO DEVELOP NWWD ACROSS ERN
   KY...WITH ALL OF THESE STORMS BEING FED BY W/NWLY LOW LEVEL WINDS
   PROVIDING AN INFLUX OF RESIDUAL MODERATE INSTABILITY RESIDING ACROSS
   KY AND MIDDLE/ERN TN.  35 KT NWLY MIDLEVEL WINDS ARE CONTRIBUTING TO
   SUFFICIENT EFFECTIVE BULK SHEAR FOR SOME ORGANIZATION AND SEWD
   MOVEMENT AS OBSERVED IN THE SWRN VA TSTM CLUSTER.
   
   THE DOWNSTREAM AIR MASS ACROSS WRN NC IS LESS UNSTABLE GIVEN TIME OF
   DAY AND EARLIER CONVECTIVE OVERTURNING.  THE LAST FEW RUNS OF THE
   HRRR SUGGEST THE ERN KY/SWRN VA STORMS WILL TRACK SEWD...BUT WEAKEN
   AS THEY REACH AREAS OF GREATER DOWNSTREAM STABILIZATION.
   
   ..PETERS/THOMPSON.. 07/25/2012
   
   
   ATTN...WFO...RNK...RLX...CAE...GSP...MRX...JKL...
   
   LAT...LON   37138161 35738063 35018077 35258202 35688234 36438273
               36658288 37238315 37138161