

000 

WWUS20 KWNS 091752

SEL5

SPC WW 091752

NYZ000-LEZ000-100100-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 495

NWS STORM PREDICTION CENTER NORMAN OK

150 PM EDT MON JUL 9 2007



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       WESTERN AND CENTRAL NEW YORK

       LAKE ERIE



EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 150 PM UNTIL 900

PM EDT.



HAIL TO 1.5 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 125

STATUTE MILES EAST AND WEST OF A LINE FROM 40 MILES NORTH OF

UTICA NEW YORK TO 10 MILES SOUTH SOUTHWEST OF ELMIRA 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 494...



DISCUSSION...SCATTERED THUNDERSTORMS WILL LIKELY FORM THIS AFTERNOON

ALONG THE LAKE BREEZE BOUNDARIES FROM ERIE AND ONTARIO...AND ALONG A

CONFLUENCE BAND INTO CENTRAL NY.  ADDITIONAL CONVECTION MAY MOVE

INTO WRN NY FROM ONTARIO...AS WELL.  MODERATE-STRONG INSTABILITY IS

PRESENT ACROSS CENTRAL AND WRN NY WHERE MLCAPE VALUES EXCEED 2000

J/KG...WHILE 40 KT MID LEVEL FLOW IS CONTRIBUTING TO SUFFICIENT

VERTICAL SHEAR FOR ORGANIZED SEVERE STORMS.  THE STRONGER STORMS

WILL BE CAPABLE OF PRODUCING DAMAGING WINDS AND HAIL...AS CONVECTION

SPREADS EWD INTO ERN NY LATER THIS AFTERNOON.



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

TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

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

MOTION VECTOR 28030.





...THOMPSON

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