

316 

WWUS20 KWNS 261842

SEL7

SPC WW 261842

CTZ000-DCZ000-DEZ000-MDZ000-NJZ000-NYZ000-PAZ000-VAZ000-WVZ000-CWZ00

0-270200-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 517

NWS STORM PREDICTION CENTER NORMAN OK

245 PM EDT FRI JUN 26 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       SOUTHERN CONNECTICUT

       DISTRICT OF COLUMBIA

       DELAWARE

       MUCH OF MARYLAND

       NEW JERSEY

       SOUTHEAST NEW YORK INCLUDING LONG ISLAND

       SOUTHERN PENNSYLVANIA

       NORTHERN VIRGINIA

       EASTERN WEST VIRGINIA PANHANDLE

       COASTAL WATERS



EFFECTIVE THIS FRIDAY AFTERNOON AND EVENING FROM 245 PM UNTIL

1000 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 95

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 65 MILES EAST

SOUTHEAST OF ISLIP NEW YORK TO 40 MILES SOUTHWEST OF ALTOONA

PENNSYLVANIA.  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.



OTHER WATCH INFORMATION...CONTINUE...WW 515...WW 516...



DISCUSSION...SCATTERED THUNDERSTORMS ARE INCREASING ACROSS PARTS OF

PA/MD/NY IN A VERY MOIST AND UNSTABLE AIRMASS.  THESE STORMS WILL

PROPAGATE SOUTHEASTWARD TOWARD THE COAST THROUGH THE AFTERNOON AND

EVENING.  DEGREE OF INSTABILITY AND SUFFICIENT DEEP LAYER EFFECTIVE

SHEAR WILL PROMOTE A RISK OF DAMAGING WINDS AND HAIL IN THE

STRONGEST CELLS.



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 500. MEAN STORM

MOTION VECTOR 29025.





...HART

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