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WWUS20 KWNS 281201

SEL1

SPC WW 281201

ALZ000-ARZ000-MSZ000-TNZ000-VAZ000-281900-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 31

NWS STORM PREDICTION CENTER NORMAN OK

700 AM EST MON FEB 28 2011



THE NWS STORM PREDICTION CENTER HAS ISSUED A

TORNADO WATCH FOR PORTIONS OF



       NORTHERN ALABAMA

       FAR EASTERN ARKANSAS

       NORTHERN MISSISSIPPI

       MIDDLE AND EASTERN TENNESSEE

       FAR WESTERN VIRGINIA



EFFECTIVE THIS MONDAY MORNING AND AFTERNOON FROM 700 AM UNTIL 200

PM EST.



TORNADOES...HAIL TO 1 INCH IN DIAMETER...THUNDERSTORM WIND GUSTS

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



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 115 STATUTE

MILES EAST AND WEST OF A LINE FROM 50 MILES NORTH NORTHWEST OF

CROSSVILLE TENNESSEE TO 15 MILES SOUTHEAST OF GREENWOOD

MISSISSIPPI.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU1).



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 28...WW 29...WW 30...



DISCUSSION...COMPLEX STORM EVOLUTION IS ONGOING IN ADVANCE OF POTENT

MIDLEVEL TROUGH AND ASSOCIATED 80-100 KT MIDLEVEL JET STREAK MOVING

THROUGH THE OZARK PLATEAU.  AMBIENT AIR MASS IS WARM AND RATHER

MOIST WITH MLCAPE VALUES OF 500-1000 J/KG AND LITTLE OR NO

CONVECTIVE INHIBITION.  AREA VWPS CONTINUE TO SHOW VERY STRONG LOW

AND DEEP-LAYER SHEAR IN PLACE ACROSS REGION WITH 0-1 KM SRH VALUES

OF 300-500 M2/S2.  AS SUCH...THE POTENTIAL WILL EXIST FOR EMBEDDED

SUPERCELL AND/OR BOWING STRUCTURES WITH A RISK FOR TORNADOES

/POSSIBLY STRONG/ AND DAMAGING WINDS.



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

SURFACE AND ALOFT TO 1 INCH. EXTREME TURBULENCE AND SURFACE WIND

GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500.

MEAN STORM MOTION VECTOR 25040.





...MEAD

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