SEL5
   
   URGENT - IMMEDIATE BROADCAST REQUESTED
   TORNADO WATCH NUMBER 915
   NWS STORM PREDICTION CENTER NORMAN OK
   325 AM CST TUE DEC 7 2004
   
   THE NWS STORM PREDICTION CENTER HAS ISSUED A
   TORNADO WATCH FOR PORTIONS OF 
   
          NORTHERN AND WESTERN ALABAMA
          EAST CENTRAL MISSISSIPPI
   
   EFFECTIVE THIS TUESDAY MORNING FROM 325 AM UNTIL 800 AM CST.
   
   TORNADOES...HAIL TO 0.5 INCH IN DIAMETER...THUNDERSTORM WIND GUSTS
   TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.
   
   THE TORNADO WATCH AREA IS ALONG AND 55 STATUTE MILES EAST AND WEST
   OF A LINE FROM 40 MILES EAST OF MERIDIAN MISSISSIPPI TO 25 MILES
   NORTH NORTHEAST OF HUNTSVILLE ALABAMA.
   
   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 914...
   
   DISCUSSION...COMPLEX SQUALL LINE WITH EMBEDDED SUPERCELL/LEWP
   STRUCTURES WILL CONTINUE TO MOVE EWD FROM MS INTO AL THROUGH THE
   EARLY MORNING HOURS.  WEAK SURFACE BASED INSTABILITY PERSISTS S OF A
   WARM FRONT ACROSS NRN AL...WHILE THE STRONGEST PRESSURE FALLS AND
   FORCING FOR ASCENT ARE BEGINNING TO SPREAD NEWD FROM NE MS/NW AL
   TOWARD TN.  EXPECT THE SQUALL LINE TO MAINTAIN INTENSITY FOR A FEW
   MORE HOURS WITH THE THREAT FOR DAMAGING WINDS WITH EMBEDDED BOWING
   SEGMENTS.  ADDITIONALLY...THE VERY STRONG LOW-LEVEL SHEAR MAY
   SUPPORT A COUPLE OF TORNADOES...ESPECIALLY NEAR THE WARM FRONT
   ACROSS NWRN/NRN AL BEFORE LOW-LEVEL SHEAR BEGINS TO WEAKEN AFTER
   SUNRISE.
   
   AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
   SURFACE AND ALOFT TO 0.5 INCH. EXTREME TURBULENCE AND SURFACE WIND
   GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 450.
   MEAN STORM MOTION VECTOR 24045.
   
   
   ...THOMPSON