

903 

WWUS20 KWNS 112147

SEL1

SPC WW 112147

MDZ000-PAZ000-VAZ000-WVZ000-120300-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 631

NWS STORM PREDICTION CENTER NORMAN OK

550 PM EDT MON JUL 11 2011



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       MARYLAND PANHANDLE

       SOUTH-CENTRAL PENNSYLVANIA

       NORTHERN VIRGINIA

       EASTERN WEST VIRGINIA



EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 550 PM UNTIL

1100 PM EDT.



HAIL TO 1 INCH IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70

MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 45

STATUTE MILES EAST AND WEST OF A LINE FROM 20 MILES WEST

NORTHWEST OF ALTOONA PENNSYLVANIA TO 10 MILES EAST SOUTHEAST OF

STAUNTON VIRGINIA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU1).



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 628...WW 629...WW 630...



DISCUSSION...LONG-LIVED MCS WITH WELL-ESTABLISHED COLD POOL WILL

CONTINUE TO PROGRESS EWD/SEWD THIS EVENING INTO A HOT AND MOIST

INFLOW AIR MASS.  WHILE SOME HAIL IS POSSIBLE...DAMAGING WINDS WILL

BE THE PRIMARY HAZARD.



AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT

TO 1 INCH. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60 KNOTS.

A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM MOTION

VECTOR 28030.





...MEAD

