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000 

WWUS20 KWNS 301909

SEL3

SPC WW 301909

MAZ000-MEZ000-NHZ000-NYZ000-VTZ000-310100-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 663

NWS STORM PREDICTION CENTER NORMAN OK

310 PM EDT THU AUG 30 2007



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       WESTERN MASSACHUSETTS

       WEST AND SOUTHERN MAINE

       NEW HAMPSHIRE

       EASTERN NEW YORK

       CENTRAL AND SOUTHERN VERMONT



EFFECTIVE THIS THURSDAY AFTERNOON AND EVENING FROM 310 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 65

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 45 MILES WEST

NORTHWEST OF ALBANY NEW YORK TO 15 MILES EAST OF AUGUSTA MAINE.

FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU3).



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...BROAD AREA OF MID LEVEL HEIGHTS FALLS WILL OVERSPREAD

THE NORTHEAST AHEAD OF PROGRESSIVE TROUGH MOVING ACROSS ONTARIO/WRN

QUEBEC ATTM.  THIS IS HELPING DRIVE A SURFACE COLD SEWD INTO NEW

ENGLAND...WHERE PREFRONTAL TEMPERATURES WILL REACH INTO THE UPPER

80S/LOWER 90S IN SOME LOCATIONS.  RESULTANT MODERATE INSTABILITY AND

MODEST SWLY FLOW ALOFT/SHEAR WILL CONTINUE TO SUPPORT STRONG TO

SEVERE STORMS...INCLUDING A FEW ORGANIZED LINES/CLUSTERS AND

POSSIBLY A SUPERCELL OR TWO.  DAMAGING WINDS AND LARGE HAIL SHOULD

ACCOMPANY THE MORE INTENSE STORMS.



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 26020.





...EVANS

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