

000 

WWUS20 KWNS 220157

SEL2

SPC WW 220157

OKZ000-220700-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 212

NWS STORM PREDICTION CENTER NORMAN OK

900 PM CDT MON APR 21 2008



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       CENTRAL AND SOUTHERN OKLAHOMA



EFFECTIVE THIS MONDAY NIGHT AND TUESDAY MORNING FROM 900 PM UNTIL

200 AM CDT.



TORNADOES...HAIL TO 2.5 INCHES IN DIAMETER...THUNDERSTORM WIND

GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE

AREAS.



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 45 STATUTE

MILES EAST AND WEST OF A LINE FROM 45 MILES NORTH OF CHANDLER

OKLAHOMA TO 10 MILES SOUTH OF ARDMORE OKLAHOMA.  FOR A COMPLETE

DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE UPDATE

(WOUS64 KWNS WOU2).



REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR

TORNADOES AND 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.



OTHER WATCH INFORMATION...CONTINUE...WW 211...



DISCUSSION...ISOLATED TSTM IN SW OK THAT FORMED EARLIER THIS EVENING

ALONG MERGING PREFRONTAL BOUNDARIES APPEARS TO HAVE BECOME A

SUSTAINED SUPERCELL.  GIVEN INCREASINGLY MOIST LOW-LEVEL

ENVIRONMENT... POTENTIAL FOR A SLIGHT NOCTURNAL INCREASE IN THE SLY

LLJ...AND GRAZING INFLUENCE OF ERN CO/WRN KS UPR TROUGH...THREAT

WILL EXIST FOR A TORNADO OR TWO IN ADDITION TO VERY LARGE HAIL AND

LOCALLY DMGG WIND.



AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL

SURFACE AND ALOFT TO 2.5 INCHES. EXTREME TURBULENCE AND SURFACE

WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO

500. MEAN STORM MOTION VECTOR 26020.





...CORFIDI

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