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000 

WWUS20 KWNS 082235

SEL9

SPC WW 082235

OKZ000-TXZ000-090300-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 259

NWS STORM PREDICTION CENTER NORMAN OK

530 PM CDT TUE MAY 8 2007



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       SOUTHWEST OKLAHOMA

       NORTHWEST AND NORTH CENTRAL TEXAS



EFFECTIVE THIS TUESDAY AFTERNOON AND EVENING FROM 530 PM UNTIL

1000 PM CDT.



TORNADOES...HAIL TO 1.5 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 60 STATUTE

MILES EAST AND WEST OF A LINE FROM 60 MILES WEST OF MINERAL WELLS

TEXAS TO 20 MILES NORTH OF FORT SILL OKLAHOMA.  FOR A COMPLETE

DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE UPDATE

(WOUS64 KWNS WOU9).



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 257...WW 258...



DISCUSSION...SCTD DISCRETE STORMS/SMALL SUPERCELLS HAVE FORMED OVER

NW TX IN HEATED AREA AHEAD OF W TX MCS.  ENHANCED SLY LLJ/ASCENT

EXISTS AHEAD OF MCS.  COUPLED WITH BACKED NEAR-SFC FLOW N OF W-E

ORIENTED OUTFLOW BOUNDARY OVER N TX...AND MOIST ENVIRONMENT INVOF

BOUNDARY...SETUP SUGGESTS A POTENTIAL FOR TORNADOES UNTIL MCS

OUTFLOW OVERTAKES REGION LATER THIS EVENING.  ISOLATED TORNADOES MAY

ALSO OCCUR NEAR INTERSECTION OF MCS LEADING EDGE WITH OUTFLOW

BOUNDARY.



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

SURFACE AND ALOFT TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE

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

500. MEAN STORM MOTION VECTOR 21025.





...CORFIDI

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