URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 308
NWS STORM PREDICTION CENTER NORMAN OK
210 PM EDT THU JUN 13 2013

THE NWS STORM PREDICTION CENTER HAS ISSUED A

* SEVERE THUNDERSTORM WATCH FOR PORTIONS OF 
  SOUTHERN MARYLAND
  EASTERN NORTH CAROLINA
  SOUTHEAST VIRGINIA
  COASTAL WATERS

* EFFECTIVE THIS THURSDAY AFTERNOON AND EVENING FROM 210 PM UNTIL
  1000 PM EDT.

...THIS IS A PARTICULARLY DANGEROUS SITUATION...

* PRIMARY THREATS INCLUDE...
  NUMEROUS SIGNIFICANT DAMAGING WIND GUSTS TO 80 MPH LIKELY
  SEVERAL VERY LARGE HAIL EVENTS TO 3 INCHES IN DIAMETER POSSIBLE
  A FEW TORNADOES POSSIBLE

THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 90
STATUTE MILES EITHER SIDE OF A LINE FROM 20 MILES NORTH NORTHWEST
OF NORFOLK VIRGINIA TO 35 MILES SOUTH SOUTHWEST OF SOUTHERN PINES
NORTH CAROLINA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU8).

PRECAUTIONARY/PREPAREDNESS ACTIONS...

REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY
DO PRODUCE TORNADOES.

&&

OTHER WATCH INFORMATION...CONTINUE...WW 306...WW 307...

DISCUSSION...AFTERNOON SURFACE OBSERVATIONS AND OBJECTIVE ANALYSIS
GUIDANCE INDICATE THE ENVIRONMENT FROM SOUTHEAST VA AND SOUTHERN
MARYLAND SOUTH ACROSS EASTERN NC HAS BECOME VERY UNSTABLE WITH
MLCAPE VALUES FROM 2500 TO OVER 4000 J/KG...AND DCAPE WELL IN EXCESS
OF 1000 J/KG. MEANWHILE...AREA VWP/S SHOW DEEP-LAYER WLY FLOW
INCREASING TO 50KT AT 3 KM AGL. GIVEN THIS COMBINATION OF STRONG TO
LOCALLY EXTREME CAPE...INCREASING SHEAR...AND ONGOING ORGANIZING
CONVECTIVE LINE AND FORCING IN THE PROCESS OF CRESTING THE
APPALACHIANS...A REGIONAL SEVERE WEATHER OUTBREAK APPEARS QUITE
LIKELY.

OVER THE NEXT SEVERAL HOURS EXPECT MULTICELL CLUSTERS/LINE SEGMENTS
AND SUPERCELLS TO SPREAD EAST ACROSS THE UNSTABLE WARM SECTOR WITH A
WIDE RANGE OF SEVERE WEATHER INCLUDING POTENTIALLY DAMAGING HAIL AND
PERHAPS EVEN A TORNADO OR TWO. AT THIS TIME...THE GREATEST HAZARD
APPEARS TO BE WIDESPREAD HIGH WINDS WITH THE CHANCE FOR DAMAGING
GUSTS IN EXCESS OF HURRICANE FORCE /65KT/. THE CORRIDOR OF GREATEST
SEVERE POTENTIAL WILL BE AROUND THE VA/NC BORDER AREA WITH A
DECREASING CHANCE FOR HIGHER-END SEVERE AND LOWER STORM COVERAGE
POSSIBLE WITH SOUTHWESTWARD EXTENT.

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 3 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 70
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 600. MEAN STORM
MOTION VECTOR 29040.


...CARBIN