MESOSCALE DISCUSSION 1078
   NWS STORM PREDICTION CENTER NORMAN OK
   0238 PM CDT FRI JUN 12 2009
   
   AREAS AFFECTED...PARTS OF CNTRL AND NRN AL
   
   CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 
   
   VALID 121938Z - 122045Z
   
   SEVERE POTENTIAL IS INCREASING THIS AFTERNOON ACROSS PARTS OF CNTRL
   AND NRN AL.  A WW IS LIKELY IN THE NEAR TERM THIS AFTERNOON BEFORE A
   RENEWED SEVERE THREAT OCCURS WITH APPROACHING DERECHO TOWARDS EARLY
   EVENING.
   
   RADAR MOSAIC SHOWS STRONG/SEVERE TSTMS DEVELOPING OVER PARTS OF NRN
   MS.  THESE STORMS HAVE DEVELOPED ALONG RESIDUAL BAROCLINIC ZONE
   EXTENDING FROM THE SRN APPALACHIANS AND DRAPING WWD INTO CNTRL AR. 
   INCREASING LARGE SCALE ASCENT ASSOCIATED WITH APPROACHING SHORTWAVE
   TROUGH --LIKELY AIDED BY PRONOUNCED MID-LEVEL CIRCULATION SPAWNED BY
   ONGOING DERECHO-- WILL CONTINUE TO OVERSPREAD THE AREA THIS
   AFTERNOON/EARLY EVENING AND FAVOR CONTINUED TSTM DEVELOPMENT ON
   PERIPHERY OF EML PLUME ORIGINATING FROM AREAS W.
   
   DESPITE WEAK TO MARGINAL SHEAR OVER THE AREA
   MID-AFTERNOON...STRONGER MID-LEVEL FLOW OVER NERN MS /PER RECENT
   KGWX VWP 35-40 KTS AT 6 KM/ WILL BEGIN TO OVERSPREAD WRN PORTIONS OF
   THE HIGHLIGHTED AREA.  A POTENTIALLY STRONGLY UNSTABLE AIRMASS WILL
   LIKELY BE REALIZED AS STORMS /INCLUDING SUPERCELLS/ MOVE EWD INTO
   AREA AHEAD OF FORWARD PROPAGATING DERECHO.  THESE SEMI-DISCRETE
   STORMS MAY MERGE INTO A SMALL CLUSTER WITH TIME...POSING BOTH A
   LARGE HAIL AND DMGG WIND THREAT.
   
   ..SMITH.. 06/12/2009
   
   
   ATTN...WFO...BMX...HUN...
   
   LAT...LON   33108631 32998673 33118770 33288819 34868799 34938770
               34778707 34638650 34308604 33988591 33508604 33108631