MESOSCALE DISCUSSION 1433
   NWS STORM PREDICTION CENTER NORMAN OK
   0144 PM CDT TUE JUN 28 2011
   
   AREAS AFFECTED...SERN WV...CNTRL/SRN VA...ERN TN...MUCH OF NC...FAR
   NWRN SC
   
   CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 
   
   VALID 281844Z - 282015Z
   
   THE THREAT FOR SVR THUNDERSTORMS WITH DMGG WINDS WILL OCCUR THIS
   AFTERNOON...AND THE ISSUANCE OF A SVR TSTM WATCH IS POSSIBLE.
   
   THE COMBINED EFFECTS OF OROGRAPHIC INFLUENCES OVER THE CNTRL/SRN
   APPALACHIANS AND A SUBTLE PREFRONTAL WIND SHIFT AXIS HAVE PROMPTED
   THE RECENT DEVELOPMENT OF INTENSE CONVECTIVE CLUSTERS NEAR THE SERN
   WV AND WRN VA BORDER...WITH MORE WIDELY SCATTERED ACTIVITY FARTHER
   SOUTH INTO ERN TN...WRN NC...AND FAR NWRN SC. THE AIR MASS ACROSS
   MUCH OF THE DISCUSSION AREA HAS BECOME MODERATELY UNSTABLE...OWING
   TO SFC TEMPERATURES HAVING CLIMBED INTO THE LOWER/MIDDLE 90S AMIDST
   DEWPOINTS IN THE UPPER 60S TO THE LOWER 70S. WITH THIS
   INSTABILITY...RECENT VISIBLE SATELLITE IMAGES REVEAL CUMULUS
   CONVERGENCE LINES SCATTERED ACROSS THE AREA EAST OF THE
   AFOREMENTIONED CONVECTION. DEEPER CONVECTIVE PLUMES COULD EVOLVE
   FROM THESE CONVERGENCE LINES IN RESPONSE TO CONTINUED INSOLATION BY
   20Z...AS AFFIRMED IN RECENT RUNS OF THE EXPERIMENTAL HRRR. AN INLAND
   SEA BREEZE BOUNDARY INVOF THE ATLANTIC COAST COULD ALSO PROVIDE A
   FOCUS FOR CONVECTIVE DEVELOPMENT THIS AFTERNOON. 
   
   THE DISCUSSION AREA LIES TO THE SOUTH OF THE STRONGER MID-LEVEL FLOW
   ATTENDANT TO THE SHORTWAVE TROUGH CENTERED OVER THE GREAT LAKES
   REGION...WHICH SHOULD LIMIT THE MAGNITUDE OF VERTICAL WIND SHEAR AND
   OVERALL CONVECTIVE ORGANIZATION. HOWEVER...WITH DCAPE VALUES IN
   EXCESS OF 900 J/KG ACROSS MUCH OF THE REGION...STRONG DOWNWARD
   CONVECTIVE BUOYANCY COULD FAVOR INTENSE WET MICROBURSTS CAPABLE OF
   DMGG WIND GUSTS. SHOULD ONE OR MORE CORRIDORS OF LOCAL UPSCALE
   GROWTH AND DMGG WIND THREAT BECOME EVIDENT IN RESPONSE TO MERGING
   COLD POOLS...THEN THE NEED FOR A SVR TSTM WATCH COULD INCREASE.
   
   ..COHEN.. 06/28/2011
   
   
   ATTN...WFO...AKQ...MHX...LWX...RAH...ILM...RNK...RLX...CAE...
   GSP...MRX...
   
   LAT...LON   34918125 34818204 34908271 35068311 35218331 35628358
               36118329 36808247 37618136 38068077 38477999 38737915
               38507772 37697655 36607615 35977618 34997672 34367808
               34897995 34918125