

265 

WWUS20 KWNS 281742

SEL8

SPC WW 281742

ALZ000-LAZ000-MSZ000-TNZ000-290200-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 108

NWS STORM PREDICTION CENTER NORMAN OK

1240 PM CDT MON APR 28 2014



THE NWS STORM PREDICTION CENTER HAS ISSUED A



* TORNADO WATCH FOR PORTIONS OF

  NORTH AND NORTHWEST ALABAMA

  NORTHEAST LOUISIANA

  CENTRAL AND NORTHEAST MISSISSIPPI

  SOUTHERN MIDDLE TENNESSEE



* EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 1240 PM UNTIL

  900 PM CDT.



...THIS IS A PARTICULARLY DANGEROUS SITUATION...



* PRIMARY THREATS INCLUDE...

  NUMEROUS TORNADOES EXPECTED WITH A FEW INTENSE TORNADOES LIKELY

  WIDESPREAD LARGE HAIL EXPECTED WITH ISOLATED VERY LARGE HAIL

    EVENTS TO 3 INCHES IN DIAMETER LIKELY

  SCATTERED DAMAGING WIND GUSTS TO 70 MPH LIKELY



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 75 STATUTE

MILES EAST AND WEST OF A LINE FROM 65 MILES NORTH OF HUNTSVILLE

ALABAMA TO 10 MILES SOUTH OF NATCHEZ MISSISSIPPI.  FOR A COMPLETE

DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE UPDATE

(WOUS64 KWNS WOU8).



PRECAUTIONARY/PREPAREDNESS ACTIONS...



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...SURFACE-BASED STORMS ARE BEGINNING TO DEVELOP FROM NE

LA INTO W CENTRAL MS...WITH ADDITIONAL DEVELOPMENT EXPECTED NEWD

TOWARD NE MS/NW AL AS CLOUDS CLEAR AND THE LOW LEVELS DESTABILIZE.

A COMBINATION OF MODERATE INSTABILITY /MLCAPE NEAR 2000 J PER KG/

AND STRONG DEEP-LAYER VERTICAL SHEAR WILL SUPPORT A BROKEN BAND OF

SUPERCELLS...WHILE SOME INCREASE IN LOW-LEVEL SHEAR IS EXPECTED THIS

AFTERNOON FROM CENTRAL MS INTO NE MS/NW AL...UP TO A RESIDUAL

OUTFLOW BOUNDARY IN SRN MIDDLE TN.  SOME OF THE SUPERCELLS WILL BE

LONG-LIVED AND CAPABLE OF PRODUCING STRONG/LONG-TRACK TORNADOES...AS

WELL AS VERY LARGE HAIL.



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

SURFACE AND ALOFT TO 3 INCHES. EXTREME TURBULENCE AND SURFACE

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

550. MEAN STORM MOTION VECTOR 24035.





...THOMPSON

