MESOSCALE DISCUSSION 0660
   NWS STORM PREDICTION CENTER NORMAN OK
   0944 AM CDT THU APR 28 2011
   
   AREAS AFFECTED...THE DELMARVA INTO SRN VA
   
   CONCERNING...TORNADO WATCH 251...
   
   VALID 281444Z - 281545Z
   
   THE SEVERE WEATHER THREAT FOR TORNADO WATCH 251 CONTINUES.
   
   A NARROW AXIS OF MODERATE INSTABILITY CURRENTLY EXTENDS NWD ACROSS
   ERN VA TOWARD THE DELMARVA.  THIS AIRMASS IS SUFFICIENTLY SHEARED
   FOR MAINTAINING THE ONGOING SEVERE BAND OF FRONTAL CONVECTION AS IT
   PROPAGATES TOWARD THE MIDDLE ATLANTIC COAST.  LATEST RADAR DATA
   SUGGEST FASTER-MOVING LINE SEGMENTS AND BOW-TYPE STRUCTURES HAVE
   EVOLVED OVER CNTRL VA AND THIS ACTIVITY COULD PRODUCE VERY DAMAGING
   WINDS AS IT SPREADS TOWARD THE TIDEWATER REGION.
   
   ..DARROW.. 04/28/2011
   
   
   ATTN...WFO...PHI...AKQ...LWX...RNK...
   
   LAT...LON   36548015 39647791 39647491 36567726 36548015