MESOSCALE DISCUSSION 0280
   NWS STORM PREDICTION CENTER NORMAN OK
   0910 PM CST TUE MAR 18 2003
   
   AREAS AFFECTED...ERN AND SERN MS/SWRN AND WCNTRL AL
   
   CONCERNING...SEVERE THUNDERSTORM POTENTIAL 
   
   VALID 190310Z - 190545Z
   
   SQUALL-LINE WILL CONTINUE TO MOVE INTO ERN MS AND WRN AL OVER THE
   NEXT COUPLE OF HOURS. WIND DAMAGE WILL BE POSSIBLE WITH
   MULTICELLS IN THE LINE WITH TORNADO POTENTIAL IN ISOLATED
   SUPERCELLS AHEAD OF THE LINE. A NEW TORNADO WATCH MAY BE REQUIRED
   FARTHER E SOON.
   
   THE STRENGTHENING LOW-LEVEL JET OVER ECNTRL MS OF 35 KNOTS AND
   APPROACHING MID-LEVEL SPEED MAX OF 80 KNOTS OVER THE NWRN GULF OF
   MEXICO WERE COMBINING TO CREATE FAVORABLE DEEP LAYER SHEAR FOR
   SUPERCELLS ACROSS ERN MS AND WRN AL. REGIONAL VAD WIND PROFILES
   SHOW STORM RELATIVE HELICITY VALUES HAVE INCREASED TO NEARLY 500
   M2/S2 IN THE LAST COUPLE OF HOURS. DUE TO INCREASING LOW-LEVEL
   WIND SHEAR PROFILES...CELLS THAT MAY DEVELOP AHEAD OF THE
   SQUALL-LINE MOVING INTO ERN MS AND WRN AL WILL HAVE A POTENTIAL
   FOR ISOLATED TORNADOES.
   
   ..BROYLES.. 03/19/2003
   
   
   ATTN...WFO...BMX...MOB...JAN...LIX...
   
   30388880 30748907 31468906 32348888 33058863 33488795
   33328697 32278653 31078691 30328734 30278830 30348875