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108 

WWUS20 KWNS 081403

SEL4

SPC WW 081403

NYZ000-LOZ000-081900-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 634

NWS STORM PREDICTION CENTER NORMAN OK

1005 AM EDT SAT SEP 8 2012



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       WESTERN NEW YORK

       LAKE ONTARIO



EFFECTIVE THIS SATURDAY MORNING AND AFTERNOON FROM 1005 AM UNTIL

300 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 55

STATUTE MILES EAST AND WEST OF A LINE FROM 55 MILES NORTH

NORTHEAST OF WATERTOWN NEW YORK TO 35 MILES WEST SOUTHWEST OF

ELMIRA NEW YORK.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU4).



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.



DISCUSSION...BAND OF LOW-TOPPED CONVECTION ALONG THE COLD FRONT WILL

CONTINUE TO SPREAD EWD THROUGH THE MORNING/EARLY AFTERNOON.  DESPITE

RATHER MODEST BUOYANCY AND CLOUD COVER...THE MOIST ENVIRONMENT AND

STRONG WIND FIELDS JUST ABOVE THE SURFACE WILL PROMOTE A RISK FOR

DAMAGING WINDS.



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 400. MEAN STORM MOTION

VECTOR 27035.





...THOMPSON

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