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000 

WWUS20 KWNS 112003

SEL9

SPC WW 112003

GAZ000-NCZ000-SCZ000-120100-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 509

NWS STORM PREDICTION CENTER NORMAN OK

400 PM EDT WED JUL 11 2007



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       SOUTHEAST GEORGIA

       SOUTHERN NORTH CAROLINA

       CENTRAL AND EASTERN SOUTH CAROLINA



EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 400 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 60

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 40 MILES WEST

NORTHWEST OF SAVANNAH GEORGIA TO 45 MILES SOUTHEAST OF

FAYETTEVILLE NORTH CAROLINA.  FOR A COMPLETE DEPICTION OF THE

WATCH SEE THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU9).



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...ORGANIZED MULTICELL CLUSTER IS DEVELOPING NEAR THE

GA/SC BORDER...AND THIS CONVECTION WILL LIKELY INCREASE IN COVERAGE

THE NEXT FEW HOURS THROUGH STORM MERGERS.  HOT SURFACE TEMPERATURES

AND STEEP LOW-LEVEL LAPSE RATES IN ADVANCE OF THIS

CONVECTION...ALONG WITH BACKGROUND FLOW OF 30-40 KT IN THE LOW TO

MID LEVELS...SHOULD SUPPORT A THREAT FOR DAMAGING DOWNBURST WINDS

AND MARGINALLY SEVERE HAIL ACROSS SE GA/SC AND PERHAPS INTO SRN NC

THIS EVENING.  THE SEVERE STORM THREAT MAY ALSO INCREASE JUST INLAND

FROM THE COAST LATE THIS AFTERNOON AS CONVECTION INTERACTS WITH THE

SEA BREEZE FRONT.



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 26035.





...THOMPSON

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