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917 

WWUS20 KWNS 081642

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CTZ000-MAZ000-NYZ000-PAZ000-VTZ000-090200-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 637

NWS STORM PREDICTION CENTER NORMAN OK

1240 PM EDT SAT SEP 8 2012



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       EXTREME NORTHWESTERN CONNECTICUT

       EXTREME WESTERN MASSACHUSETTS

       CENTRAL AND EASTERN NEW YORK

       NORTHEAST PENNSYLVANIA

       VERMONT



EFFECTIVE THIS SATURDAY AFTERNOON AND EVENING FROM 1240 PM UNTIL

1000 PM EDT.



TORNADOES...HAIL TO 1 INCH IN DIAMETER...THUNDERSTORM WIND GUSTS

TO 80 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 70 STATUTE

MILES EAST AND WEST OF A LINE FROM 40 MILES SOUTHWEST OF

MONTICELLO NEW YORK TO 40 MILES NORTH OF BURLINGTON VERMONT.  FOR

A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU7).



REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR

TORNADOES AND 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.



OTHER WATCH INFORMATION...CONTINUE...WW 634...WW 635...WW 636...



DISCUSSION...A SQUALL LINE ALONG THE SURFACE COLD FRONT...AS WELL AS

OTHER STORMS IN ALONG A PRE-FRONTAL DIFFERENTIAL HEATING ZONE...WILL

INTENSIFY THROUGH THE AFTERNOON AS THE FRONT APPROACHES AN AREA OF

GREATER MOISTURE/INSTABILITY.  MEANWHILE...VERTICAL SHEAR PROFILES

WILL CONTINUE TO STRENGTHEN THROUGH THE AFTERNOON AS STRONG MIDLEVEL

TROUGH EJECTS NEWD FROM THE UPPER OH VALLEY.  THE NET RESULT WILL BE

AN ENVIRONMENT FAVORABLE FOR WIDESPREAD DAMAGING WINDS AND EMBEDDED

TORNADIC CIRCULATIONS WITHIN THE FRONTAL SQUALL LINE...AS WELL AS

MORE DISCRETE SUPERCELLS WITH AN ASSOCIATED TORNADO RISK ALONG A

PRE-FRONTAL CONFLUENCE BAND ACROSS SE NY/WRN MA/WRN CT.



AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL

SURFACE AND ALOFT TO 1 INCH. EXTREME TURBULENCE AND SURFACE WIND

GUSTS TO 70 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 450.

MEAN STORM MOTION VECTOR 25045.





...THOMPSON

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