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000 

WWUS20 KWNS 231926

SEL9

SPC WW 231926

DCZ000-MDZ000-NCZ000-VAZ000-WVZ000-CWZ000-240300-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 739

NWS STORM PREDICTION CENTER NORMAN OK

325 PM EDT WED JUL 23 2008



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       DISTRICT OF COLUMBIA

       MUCH OF MARYLAND

       PARTS OF WESTERN NORTH CAROLINA

       PARTS OF WESTERN VIRGINIA

       SMALL PART OF EASTERN WEST VIRGINIA

       COASTAL WATERS



EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 325 PM UNTIL

1100 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 65

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

NORTHWEST OF BALTIMORE MARYLAND TO 15 MILES WEST SOUTHWEST OF

CHARLOTTE 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.



OTHER WATCH INFORMATION...CONTINUE...WW 735...WW 736...WW

737...WW 738...



DISCUSSION...THUNDERSTORMS INCREASING ALONG AND AHEAD OF COLD FRONT

NOW CROSSING APPALACHIANS.  WITH CLOUDS CLEARING...AIR MASS ACROSS

WATCH AREA IS NOW BECOMING UNSTABLE AND WEAKLY CAPPED.  WITH STRONG

UPPER TROUGH APPROACHING  FROM OH VALLEY...SHEAR AND LARGE SCALE

ASCENT SUPPORTS INCREASING WIND DAMAGE POTENTIAL ALONG WITH

MARGINALLY SEVERE HAIL AS STORMS SPREAD E OMTNS.



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 550. MEAN STORM

MOTION VECTOR 27030.





...HALES

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