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095 

WWUS20 KWNS 290756

SEL8

SPC WW 290756

NYZ000-OHZ000-PAZ000-LEZ000-291600-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 698

NWS STORM PREDICTION CENTER NORMAN OK

350 AM EDT FRI JUL 29 2011



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       WESTERN NEW YORK

       NORTHERN OHIO

       NORTHWEST PENNSYLVANIA

       LAKE ERIE



EFFECTIVE THIS FRIDAY MORNING FROM 350 AM UNTIL NOON EDT.



HAIL TO 0.5 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 100

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

NORTHEAST OF BUFFALO NEW YORK TO 30 MILES WEST OF CLEVELAND 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 697...



DISCUSSION...CORRIDOR OF HIGH PW AND RICH LOW LVL MOISTURE

COINCIDENT WITH STRENGTHENING UNIDIRECTIONAL WLY FLOW /WITH SPEEDS

INCREASING TO 40-50 KTS IN THE 700-500 MB LAYER OVER LK ERIE BY 12Z/

MAY SUPPORT BANDS OF STORMS WITH SMALL BOWING SEGMENTS AND A THREAT

FOR DMGG WIND.  THIS THREAT SHOULD SPREAD E FROM LWR MI/NRN IND INTO

NRN OH/LK ERIE.  OTHER MORE ISOLD SVR STORMS MAY CONTINUE TO FORM

INVOF DIFFUSE WARM FRONT OVER FAR ERN PARTS OF LK ERIE AND OVER NW

PA/WRN NY.  THESE ALSO WILL HAVE THE POTENTIAL FOR LOCALLY DMGG WIND

AS THE JET MAX CONTINUES EWD THROUGH LATE MORNING.



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

TO 0.5 INCH. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

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

MOTION VECTOR 27035.





...CORFIDI

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