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WWUS20 KWNS 250943

SEL9

SPC WW 250943

ARZ000-LAZ000-OKZ000-TXZ000-251600-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 199

NWS STORM PREDICTION CENTER NORMAN OK

445 AM CDT MON APR 25 2011



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       SOUTHWEST ARKANSAS

       NORTHWEST LOUISIANA

       SOUTHEAST OKLAHOMA

       PARTS OF NORTH CENTRAL AND NORTHEAST TEXAS



EFFECTIVE THIS MONDAY MORNING FROM 445 AM UNTIL 1100 AM CDT.



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 80

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 50 MILES SOUTH OF

DURANT OKLAHOMA TO 15 MILES NORTH OF EL DORADO ARKANSAS.  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...THIS SEVERE THUNDERSTORM WATCH REPLACES

SEVERE THUNDERSTORM WATCH NUMBER 198. WATCH NUMBER 198 WILL NOT

BE IN EFFECT AFTER 445 AM CDT.



DISCUSSION...CLUSTERS OF STRONG/SEVERE STORMS WILL LIKELY PERSIST

THROUGH THE MORNING WHILE MOVING EWD INVOF OF THE SYNOPTIC FRONT IN

N TX/SE OK AND AN E-W OUTFLOW BOUNDARY ACROSS SRN AR...AND IN

ADVANCE OF A MIDLEVEL TROUGH EJECTING EWD FROM NM.  A FEED OF

MODERATE INSTABILITY FROM THE S WILL PERSIST THROUGH THE MORNING AND

HELP MAINTAIN THE CONVECTION AND A RISK OF LARGE HAIL AND DAMAGING

WINDS FOR THE NEXT SEVERAL HOURS.



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 27035.





...THOMPSON

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