

000 

WWUS20 KWNS 101440

SEL7

SPC WW 101440

CTZ000-DEZ000-MAZ000-NJZ000-NYZ000-PAZ000-VTZ000-CWZ000-102300-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 817

NWS STORM PREDICTION CENTER NORMAN OK

1040 AM EDT SUN AUG 10 2008



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       WESTERN CONNECTICUT

       NORTHERN DELAWARE

       FAR WESTERN MASSACHUSETTS

       NEW JERSEY

       EASTERN NEW YORK

       EASTERN PENNSYLVANIA

       FAR SOUTHERN VERMONT

       COASTAL WATERS



EFFECTIVE THIS SUNDAY MORNING AND EVENING FROM 1040 AM UNTIL 700

PM EDT.



HAIL TO 2 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 50

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

PHILADELPHIA PENNSYLVANIA TO 25 MILES NORTH NORTHWEST OF GLENS

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

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU7).



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...THUNDERSTORMS WILL BECOME INCREASINGLY WIDESPREAD AS

AFTERNOON HEATING ELIMINATES SURFACE INHIBITION AND BOOSTS MLCAPE

INTO THE 1000-1500 J/KG RANGE ACROSS THIS REGION.  VERY COLD AIR

ALOFT WILL SUPPORT LARGE HAIL THREAT...ALONG WITH POTENTIAL FOR

ISOLATED DAMAGING WINDS...DESPITE THE MODEST DEEP LAYER FLOW.



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

TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 400. MEAN STORM

MOTION VECTOR 22015.





...EVANS

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