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945 

WWUS20 KWNS 181938

SEL6

SPC WW 181938

CTZ000-MAZ000-NYZ000-CWZ000-190300-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 646

NWS STORM PREDICTION CENTER NORMAN OK

340 PM EDT TUE SEP 18 2012



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       WESTERN CONNECTICUT

       WESTERN MASSACHUSETTS

       EASTERN NEW YORK

       COASTAL WATERS



EFFECTIVE THIS TUESDAY AFTERNOON AND EVENING FROM 340 PM UNTIL

1100 PM EDT.



TORNADOES...HAIL TO 0.5 INCH IN DIAMETER...THUNDERSTORM WIND

GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE

AREAS.



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 45 STATUTE

MILES EAST AND WEST OF A LINE FROM 30 MILES NORTH NORTHWEST OF

GLENS FALLS NEW YORK TO 10 MILES SOUTH SOUTHEAST OF POUGHKEEPSIE

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

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU6).



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 641...WW 642...WW

643...WW 644...WW 645...



DISCUSSION...A STRONGLY FORCED CONVECTIVE BAND OVER CNTRL NY SHOULD

CONTINUE TO STRENGTHEN AS IT PROGRESSES EWD THROUGH THE HUDSON

VALLEY THIS EVENING.  AMBIENT ENVIRONMENT IS CHARACTERIZED BY VERY

WEAK INSTABILITY...BUT INTENSE VERTICAL SHEAR AND FORCING FOR

ASCENT.  AND WHILE DAMAGING WINDS WILL BE THE PRIMARY SEVERE WEATHER

HAZARD WITH THIS CONVECTIVE BAND...TORNADOES WILL BE POSSIBLE OWING

TO THE STRONG LOW-LEVEL SHEAR AND LOW LCL/MOIST BOUNDARY LAYER.



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

SURFACE AND ALOFT TO 0.5 INCH. EXTREME TURBULENCE AND SURFACE

WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO

300. MEAN STORM MOTION VECTOR 23045.





...MEAD

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