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URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 461

NWS STORM PREDICTION CENTER NORMAN OK

425 PM EDT WED JUL 4 2012



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       EXTREME WESTERN MARYLAND PANHANDLE

       SOUTHEAST OHIO

       SOUTHWEST PENNSYLVANIA

       NORTHERN WEST VIRGINIA



EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 425 PM UNTIL

1000 PM EDT.



HAIL TO 1.5 INCHES 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 NORTH AND SOUTH OF A LINE FROM 15 MILES NORTHWEST

OF PARKERSBURG WEST VIRGINIA TO 30 MILES EAST SOUTHEAST OF

MORGANTOWN WEST 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 460...



DISCUSSION...INITIAL STORMS INVOF THE WV PANHANDLE/SE OH COULD

INCREASE SOME IN COVERAGE/INTENSITY AS DAYTIME HEATING

PERSISTS...AND STORM MERGERS/INTERACTIONS COULD EVENTUALLY LEAD TO

THE FORMATION OF A SMALL CLUSTER OF STORMS.  THE THERMODYNAMIC

ENVIRONMENT IS FAVORABLE FOR ISOLATED LARGE HAIL GIVEN MLCAPE NEAR

2500 J/KG AND A FEW DAMAGING DOWNBURSTS BASED ON STEEP LOW-LEVEL

LAPSE RATES AND LARGE DCAPE.  OVER THE NEXT FEW HOURS...STORMS

SHOULD SPREAD SWD/SEWD TOWARD WV GIVEN 20-30 KT NNWLY MIDLEVEL FLOW.



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

TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

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

MOTION VECTOR 33020.





...THOMPSON

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