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URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 667

NWS STORM PREDICTION CENTER NORMAN OK

525 PM CDT WED OCT 17 2012



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       ARKANSAS

       SOUTHERN ILLINOIS

       WESTERN KENTUCKY

       SOUTHEAST MISSOURI

       NORTHWEST MISSISSIPPI

       WESTERN TENNESSEE



EFFECTIVE THIS WEDNESDAY AFTERNOON AND THURSDAY MORNING FROM 525

PM UNTIL 200 AM CDT.



TORNADOES...HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND

GUSTS TO 75 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE

AREAS.



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 130 STATUTE

MILES EAST AND WEST OF A LINE FROM 60 MILES NORTH NORTHWEST OF

POPLAR BLUFF MISSOURI TO 30 MILES SOUTHWEST OF PINE BLUFF

ARKANSAS.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU7).



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 666...



DISCUSSION...TSTMS EXPECTED TO INCREASE RAPIDLY IN NUMBER AND EXTENT

OVER THE NEXT 1-2 HRS...ESPECIALLY FROM S CNTRL AR NEWD INTO SE

MO/SRN IL...AS LEADING EDGE OF STRONG FORCING FOR ASCENT WITH

AMPLIFYING SHORTWAVE TROUGH OVERSPREADS LOW-LVL MOIST AXIS.

STRENGTHENING...DEEP-VEERING WIND PROFILES...WITH 700 MB SPEEDS AOA

45 KTS...COUPLED WITH 40+ KT WEAKLY CONFLUENT LOW-LVL FLOW...MAY

SUPPORT A FEW LONG-LIVED SUPERCELLS POSING A SVR WIND...HAIL...AND

TORNADO THREAT THROUGH LATE TNGT. IN THE MEAN TIME...OTHER STORMS

EXPECTED TO CONTINUE FORMING ALONG SFC COLD FRONT IN NW AR. THESE

TOO MAY EVOLVE INTO SUPERCELLS WITH A RISK FOR SVR WIND...HAIL...AND

POSSIBLY A TORNADO. FINALLY...SQLN WITH EMBEDDED CIRCULATIONS

EXTENDING FROM S CNTRL MO NEWD TO NEAR ST LOUIS EXPECTED TO

ACCELERATE ENEWD...WITH A CONTINUING RISK FOR DMGG WIND AND PERHAPS

ADDITIONAL EMBEDDED SMALL SCALE CIRCULATIONS/BRIEF TORNADOES.



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

SURFACE AND ALOFT TO 2 INCHES. EXTREME TURBULENCE AND SURFACE

WIND GUSTS TO 65 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO

500. MEAN STORM MOTION VECTOR 29040.





...CORFIDI

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