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WWUS20 KWNS 051720

SEL5

SPC WW 051720

ARZ000-MOZ000-MSZ000-TNZ000-060100-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 145

NWS STORM PREDICTION CENTER NORMAN OK

1220 PM CDT THU APR 5 2012



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       FAR NORTHEAST ARKANSAS

       MISSOURI BOOTHEEL

       NORTHERN MISSISSIPPI

       WESTERN TENNESSEE



EFFECTIVE THIS THURSDAY AFTERNOON AND EVENING FROM 1220 PM UNTIL

800 PM CDT.



HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70

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



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 60

STATUTE MILES EAST AND WEST OF A LINE FROM 50 MILES NORTHEAST OF

DYERSBURG TENNESSEE TO 30 MILES SOUTH OF OXFORD MISSISSIPPI.  FOR

A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU5).



REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE

FAVORABLE FOR 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. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY

DO PRODUCE TORNADOES.



OTHER WATCH INFORMATION...CONTINUE...WW 143...WW 144...



DISCUSSION...TSTMS ARE EXPECTED TO INCREASE IN COVERAGE AND

INTENSITY THIS AFTERNOON WITHIN MIDLEVEL COLD CORE OF UPPER LOW.

DESPITE MARGINAL VERTICAL SHEAR...STEEP LAPSE RATES AND COOL

THERMODYNAMIC PROFILES WILL SUPPORT HAIL PRODUCTION WITH THE

STRONGEST STORMS.  A BRIEF TORNADO IS POSSIBLE OWING TO AMBIENT

VERTICAL VORTICITY...THOUGH ANY OCCURRENCE SHOULD BE SHORT-LIVED.



AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT

TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 400. MEAN STORM

MOTION VECTOR 24015.





...MEAD

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