

828 

WWUS20 KWNS 101915

SEL5

SPC WW 101915

NYZ000-OHZ000-PAZ000-LEZ000-LOZ000-110300-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 695

NWS STORM PREDICTION CENTER NORMAN OK

315 PM EDT MON AUG 10 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       WESTERN AND CENTRAL NEW YORK

       NORTHEAST AND EAST CENTRAL OHIO

       NORTHERN AND WESTERN PENNSYLVANIA

       LAKE ERIE

       LAKE ONTARIO



EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 315 PM UNTIL

1100 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 55

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 25 MILES WEST OF

AKRON OHIO TO 10 MILES EAST NORTHEAST OF UTICA NEW YORK.  FOR A

COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE

UPDATE (WOUS64 KWNS WOU5).



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 693...WW 694...



DISCUSSION...THUNDERSTORMS ARE DEVELOPING AND INTENSIFYING RAPIDLY

FROM THE LAKE ERIE SHORE NEWD INTO CENTRAL NY...IN ADVANCE OF A

SHORT WAVE TROUGH MOVING EWD ACROSS LOWER GREAT LAKES.  ADDITIONAL

STORMS ARE EVIDENT OVER SRN ONTARIO...AND THESE ARE EXPECTED TO MOVE

EWD OVER THE NEXT SEVERAL HOURS.  THE AIR MASS HAS BECOME MODERATELY

UNSTABLE WITH MLCAPE OF 1500-2500 J/KG SUPPORTED BY SURFACE

TEMPERATURES IN THE 80S AND DEW POINTS IN THE UPPER 60S/LOWER 70S.

WESTERLY WINDS OF 30-40 KT AND UNIDIRECTIONAL PROFILES WILL PROMOTE

ORGANIZED CONVECTIVE STORMS WITH POTENTIAL FOR BOWING LINE SEGMENTS

TO DEVELOP.



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 27030.





...WEISS

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