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WWUS20 KWNS 231707

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URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 704

NWS STORM PREDICTION CENTER NORMAN OK

1205 PM CDT SAT OCT 23 2010



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       SOUTHEAST OKLAHOMA

       CENTRAL AND NORTHERN TEXAS



EFFECTIVE THIS SATURDAY AFTERNOON AND EVENING FROM 1205 PM UNTIL

800 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 75 STATUTE

MILES EAST AND WEST OF A LINE FROM 55 MILES NORTH OF PARIS TEXAS

TO 65 MILES SOUTH SOUTHEAST OF BROWNWOOD TEXAS.  FOR A COMPLETE

DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE UPDATE

(WOUS64 KWNS WOU4).



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...THIS TORNADO WATCH REPLACES SEVERE

THUNDERSTORM WATCH NUMBER 703. WATCH NUMBER 703 WILL NOT BE IN

EFFECT AFTER 1205 PM CDT.



DISCUSSION...TSTMS SHOULD CONTINUE TO INCREASE IN COVERAGE AND

INTENSITY THIS AFTERNOON ALONG RESIDUAL OUTFLOW ASSOCIATED WITH

DECAYING NOCTURNAL MCS AS LARGE-SCALE FORCING INTENSIFIES AHEAD OF

MIDLEVEL TROUGH.  CONSIDERABLE CLOUDS AND PRECIPITATION WILL TEND TO

LIMIT THE POTENTIAL FOR MORE WIDESPREAD AND STRONGER AIR MASS

DESTABILIZATION.  HOWEVER...THE PRESENCE OF A MOIST BOUNDARY LAYER

COUPLED WITH POCKETS OF STRONGER HEATING WILL STILL YIELD AFTERNOON

MLCAPE VALUES APPROACHING 1000-1500 J/KG.  THIS INSTABILITY COUPLED

WITH SUFFICIENTLY STRONG LOW AND DEEP-LAYER SHEAR FOR STORM

ORGANIZATION/ROTATION INDICATES A THREAT FOR EMBEDDED SUPERCELLS

CAPABLE OF DAMAGING WINDS...HAIL AND A COUPLE OF TORNADOES.



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 24030.





...MEAD

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