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000 

WWUS20 KWNS 291611

SEL8

SPC WW 291611

NYZ000-OHZ000-PAZ000-WVZ000-LEZ000-LOZ000-300000-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 638

NWS STORM PREDICTION CENTER NORMAN OK

1215 PM EDT SUN JUN 29 2008



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       LARGE PART OF WESTERN NEW YORK

       PARTS OF EASTERN OHIO

       LARGE PART OF WESTERN PENNSYLVANIA

       PARTS OF NORTHERN WEST VIRGINIA

       LAKE ERIE

       LAKE ONTARIO



EFFECTIVE THIS SUNDAY AFTERNOON AND EVENING FROM 1215 PM UNTIL

800 PM EDT.



HAIL TO 2 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 65

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

WATERTOWN NEW YORK TO 45 MILES SOUTHEAST OF ZANESVILLE OHIO.  FOR

A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU8).



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 637...



DISCUSSION...THUNDERSTORMS ARE INCREASING ALONG/AHEAD OF COLD FRONT

ACROSS ERN OH. WITH MLCAPES TO 1500 J/KG AND 40KT OF DEEP LAYER

SHEAR AHEAD OF LARGE UPPER TROUGH...SEVERE THUNDERSTORMS WILL

DEVELOP AND SPREAD QUICKLY NEWD.  PRIMARY THREAT WILL BE DAMAGING

WINDS AND HAIL AS STORMS EVOLVE INTO LINE SEGMENTS/BOWS.



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

TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

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

MOTION VECTOR 23035.





...HALES

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