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403 

WWUS20 KWNS 170505

SEL2

SPC WW 170505

DCZ000-DEZ000-MDZ000-PAZ000-VAZ000-CWZ000-170900-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 742

NWS STORM PREDICTION CENTER NORMAN OK

1205 AM EST WED NOV 17 2010



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       DISTRICT OF COLUMBIA

       DELAWARE

       CENTRAL AND EASTERN MARYLAND

       SOUTHEAST PENNSYLVANIA

       NORTHEAST VIRGINIA

       COASTAL WATERS



EFFECTIVE THIS WEDNESDAY MORNING FROM 1205 AM UNTIL 400 AM EST.



HAIL TO 0.5 INCH 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 55

STATUTE MILES EAST AND WEST OF A LINE FROM 40 MILES WEST

NORTHWEST OF WILMINGTON DELAWARE TO 25 MILES WEST SOUTHWEST OF

PATUXENT RIVER MARYLAND.  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.



OTHER WATCH INFORMATION...CONTINUE...WW 741...



DISCUSSION...INCREASING LINE OF THUNDERSTORMS OVER VA/MD/CENTRAL PA

WILL TRACK RAPIDLY EASTWARD DURING THE NEXT FEW HOURS.  INSTABILITY

IS VERY WEAK...BUT APPEARS SUFFICIENT FOR THE RISK OF DAMAGING WINDS

ALONG THE LEADING EDGE OF THE CONVECTION.



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

TO 0.5 INCH. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 350. MEAN STORM

MOTION VECTOR 24040.





...HART

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