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000 

WWUS20 KWNS 101828

SEL9

SPC WW 101828

OKZ000-TXZ000-110100-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 929

NWS STORM PREDICTION CENTER NORMAN OK

1225 PM CST MON NOV 10 2008



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       EXTREME SOUTHWEST OKLAHOMA

       CENTRAL AND NORTHWEST TEXAS



EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 1225 PM UNTIL

700 PM CST.



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 65 STATUTE

MILES EAST AND WEST OF A LINE FROM 20 MILES NORTHWEST OF WICHITA

FALLS TEXAS TO 40 MILES EAST SOUTHEAST OF JUNCTION TEXAS.  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.



DISCUSSION...THUNDERSTORMS ARE BEGINNING TO DEVELOP ACROSS CENTRAL

TX WHERE LOW-LEVEL MOISTENING AND SURFACE HEATING HAVE ERODED

CONVECTIVE INHIBITION...AND ADDITIONAL THUNDERSTORM DEVELOPMENT

APPEARS LIKELY DURING THE AFTERNOON ALONG THE WARM FRONT AND DRYLINE

NEAR THE RED RIVER IN NW TX.  THOUGH MID LEVEL LAPSE RATES ARE NOT

PARTICULARLY STEEP AND CLOUDS HAVE LIMITED SURFACE HEATING THUS

FAR...GRADUAL MOISTENING AND CLOUD BREAKS W OF I-35 SHOULD ALLOW

SUFFICIENT DESTABILIZATION IN THE WARM SECTOR TO SUPPORT A SEVERE

STORM THREAT.  MLCAPE VALUES OF 500-1500 J/KG AND STRONG

LOW-LEVEL/DEEP LAYER SHEAR WILL SUPPORT SUPERCELLS CAPABLE OF

PRODUCING A FEW TORNADOES...ALONG WITH AT LEAST ISOLATED LARGE HAIL

AND DAMAGING WINDS.



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

450. MEAN STORM MOTION VECTOR 25030.





...THOMPSON

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