MESOSCALE DISCUSSION 1373
   NWS STORM PREDICTION CENTER NORMAN OK
   0438 PM CDT FRI JUN 13 2003
   
   AREAS AFFECTED...CENTRAL/ERN VA...MD...AND DC METRO AREA
   
   CONCERNING...SEVERE THUNDERSTORM POTENTIAL 
   
   VALID 132138Z - 132315Z
   
   ISOLATED SEVERE THUNDERSTORMS - WITH POTENTIAL FOR LOCALIZED SEVERE
   WIND GUSTS - ARE EXPECTED THIS EVENING ACROSS CENTRAL/ERN
   VA...MD...AND WASHINGTON DC AREA. MARGINAL/ISOLATED NATURE OF THREAT
   WILL LIKELY PRECLUDE WATCH ISSUANCE.
   
   DAYTIME HEATING AND BOUNDARY LAYER DEWPOINTS IN THE LOW TO MIDDLE
   70S HAS CONTRIBUTED TO MODERATE INSTABILITY ACROSS THE DISCUSSION
   AREA WITH 100MB MLCAPE VALUES OF 2000-2500 J/KG. A LINE OF
   CONVECTION EXTENDING FROM 30 E HGR TO 30 NE LYH AT 2130Z WILL TRACK
   ENEWD ACROSS THE DISCUSSION AREA THROUGH THIS EVENING. CONVERGENCE
   ALONG LEADING OUTFLOW BOUNDARY COUPLED WITH UNCAPPED AIR MASS SHOULD
   BE SUFFICIENT TO MAINTAIN CONVECTIVE ACTIVITY FOR SEVERE ADDITIONAL
   HOURS. ALSO...EMBEDDED VORT MAX ACROSS S-CENTRAL VA WILL LEAD TO NEW
   CELL DEVELOPMENT ACROSS ERN/SERN VA DURING THE NEXT 1-2 HOURS.
   DEEP-LAYER SHEAR VALUES /SFC-6KM/ OF 25KT PER LWX AND AKQ SUGGEST
   MARGINAL ORGANIZATION OF CONVECTION. MAGNITUDE OF INSTABILITY SHOULD
   BE SUFFICIENT FOR LOCALIZED DAMAGING WINDS WITH WET MICROBURSTS.
   HIGH WBZ HEIGHTS AROUND 12-13 KFT SUGGEST THREAT FOR LARGE HAIL WILL
   BE RELATIVELY LOW. POTENTIAL FOR SEVERE ACTIVITY WILL GRADUALLY
   DIMINISH VERY LATE THIS EVENING OWING TO BOUNDARY LAYER COOLING AS
   STORMS MOVE ENEWD TOWARD DELMARVA PENINSULA.
   
   ..BANACOS.. 06/13/2003
   
   
   ATTN...WFO...PHI...AKQ...LWX...RNK...
   
   36747735 36847858 37757915 39397742 39217641 38027560
   36777603