

079 

WWUS20 KWNS 061033

SEL2

SPC WW 061033

ARZ000-LAZ000-OKZ000-TXZ000-061800-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 252

NWS STORM PREDICTION CENTER NORMAN OK

530 AM CDT WED MAY 6 2009



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       SOUTHWESTERN ARKANSAS

       NORTHWESTERN LOUISIANA

       SOUTHERN OKLAHOMA

       NORTH-CENTRAL...NORTHEASTERN AND EASTERN TEXAS



EFFECTIVE THIS WEDNESDAY MORNING AND AFTERNOON FROM 530 AM UNTIL

100 PM CDT.



HAIL TO 1 INCH IN DIAMETER...THUNDERSTORM WIND GUSTS TO 80

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 55 MILES WEST

SOUTHWEST OF ARDMORE OKLAHOMA TO 60 MILES NORTHEAST OF

NATCHITOCHES LOUISIANA.  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...THIS SEVERE THUNDERSTORM WATCH REPLACES

SEVERE THUNDERSTORM WATCH NUMBER 249. WATCH NUMBER 249 WILL NOT

BE IN EFFECT AFTER 530 AM CDT. CONTINUE...WW 248...WW 251...



DISCUSSION...INCREASINGLY WELL-ORGANIZED BOW ECHO IN FORMER WW 249

IS BEGINNING TO PRODUCE SVR GUSTS ABOVE 50 KT AS IT MOVES OVER AND S

OF SFC WARM FRONT OUTLINED IN MESOSCALE DISCUSSION 727.  THIS MCS

SHOULD CONTINUE TO SURGE SEWD WITH POTENTIAL FOR SWATH OF DAMAGING

WIND...POSSIBLE DERECHO...OVER PORTIONS WW AREA.  COUNTY WW AREA

FANS OUTWARD WITH SEWD EXTENT TO ACCOUNT FOR POTENTIAL

SPREAD/EXPANSION OF DRIVING COLD POOL.



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

TO 1 INCH. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 70 KNOTS.

A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 600. MEAN STORM MOTION

VECTOR 30040.





...EDWARDS/EVANS

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