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000 

WWUS20 KWNS 101702

SEL5

SPC WW 101702

MAZ000-NHZ000-NYZ000-VTZ000-110100-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 505

NWS STORM PREDICTION CENTER NORMAN OK

100 PM EDT TUE JUL 10 2007



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       WESTERN AND CENTRAL MASSACHUSETTS

       WESTERN AND CENTRAL NEW HAMPSHIRE

       EASTERN NEW YORK

       VERMONT



EFFECTIVE THIS TUESDAY AFTERNOON AND EVENING FROM 100 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 80

STATUTE MILES EAST AND WEST OF A LINE FROM 35 MILES NORTH OF

BURLINGTON VERMONT TO 35 MILES SOUTH SOUTHWEST OF PITTSFIELD

MASSACHUSETTS.  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 504...



DISCUSSION...TSTMS ARE EXPECTED TO INCREASE IN COVERAGE AND

INTENSITY THIS AFTERNOON WITHIN MOIST AND MODERATELY UNSTABLE

LOW-LEVEL AIR MASS WITH MLCAPES OF 2000-3000 J/KG.  THIS INSTABILITY

COUPLED WITH MODEST DEEP LAYER SHEAR /30-40KT OF EFFECTIVE BULK

SHEAR/ INDICATE THE POTENTIAL FOR ORGANIZED...SEVERE STORMS

INCLUDING A FEW SUPERCELLS CAPABLE OF DAMAGING WINDS AND LARGE HAIL.



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 27030.





...MEAD/THOMPSON

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