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