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000 

WWUS20 KWNS 171738

SEL2

SPC WW 171738

DEZ000-NJZ000-PAZ000-CWZ000-180000-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 612

NWS STORM PREDICTION CENTER NORMAN OK

135 PM EDT FRI AUG 17 2007



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NORTHERN DELAWARE

       NEW JERSEY

       EASTERN PENNSYLVANIA

       COASTAL WATERS



EFFECTIVE THIS FRIDAY AFTERNOON AND EVENING FROM 135 PM UNTIL 800

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 60

STATUTE MILES EAST AND WEST OF A LINE FROM 10 MILES NORTH OF

WILKESBARRE PENNSYLVANIA TO 15 MILES EAST SOUTHEAST OF WILMINGTON

DELAWARE.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU2).



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...STRONG STORMS HAVE DEVELOPED ALONG/NORTHEAST OF

RETREATING WARM FRONT OVER CENTRAL/ERN PA IN ADVANCE OF SHORT WAVE

TROUGH MOVING ESEWD ACROSS THE LOWER GREAT LAKES INTO WRN PARTS OF

NY AND PA.  AIR MASS IS DESTABILIZING INTO ERN PA AS SURFACE WINDS

VEER TO SWLY DIRECTION AND MOISTURE INCREASES NEWD AHEAD OF WEAK

SURFACE LOW...WITH MLCAPE OF 1000-1500 J/KG.  STRONG WLY MID LEVEL

WINDS ARE CONTRIBUTING TO DEEP LAYER SHEAR OF 40-50 KT SUPPORTIVE OF

SEVERE STORMS INCLUDING ISOLATED SUPERCELLS.  ALTHOUGH AN ISOLATED

TORNADO IS POSSIBLE PRIMARY THREATS WILL BE FOR LARGE HAIL AND

DAMAGING WINDS.



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 450. MEAN STORM

MOTION VECTOR 27030.





...WEISS

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