MESOSCALE DISCUSSION 2221
   NWS STORM PREDICTION CENTER NORMAN OK
   0703 AM CDT THU SEP 16 2004
   
   AREAS AFFECTED...AL...SWRN GA...FL PNHDL AND PARTS OF NRN FL
   
   CONCERNING...TORNADO WATCH 826...827...
   
   VALID 161203Z - 161400Z
   
   CENTER OF IVAN CONTINUES TO MOVE FARTHER INLAND AND WAS MOVING NNEWD
   ACROSS MONROE COUNTY ALABAMA EARLY THIS MORNING. EXTENSIVE
   CONVECTIVE FEEDER BANDS CONTINUE TO PINWHEEL AROUND THE CENTER OF
   THE DEEP TROPICAL CYCLONE...ESPECIALLY ACROSS THE ERN AND NERN
   PORTIONS OF THE CIRCULATION. WIND PROFILE DATA OVER A LARGE AREA OF
   AL/SRN GA AND NRN FL WERE INDICATING VERY INTENSE TO EXTREME VALUES
   OF 0-1KM HELICITY...ON THE ORDER OF 600-1200 M2/S2. JUST ABOUT ANY
   CONVECTIVE UPDRAFT IN THIS TROPICAL ENVIRONMENT WILL ACQUIRE
   ROTATION AND COULD END UP PRODUCING A TORNADO.
   
   SOME OF THE MORE INTENSE CELLS HAVE BEEN OCCURRING WITHIN AN OUTER
   RAINBAND LOCATED FROM CROSS CITY, FL TO NE OF MONTGOMERY, AL. A FEW
   ROTATING CELLS WITHIN THIS ARC OVER FL AND GA ARE OVER 200 MILES
   FROM THE CENTER OF IVAN. THIS IS AN INDICATION OF JUST HOW LARGE THE
   STRONG WIND FIELD IS WITH THIS HURRICANE.
   
   ANOTHER BAND OF INTENSE CONVECTION WITH NUMEROUS CG LIGHTNING
   STRIKES WAS NEAR THE AL/GA LINE. THIS BAND...BEING CLOSER TO THE
   CENTER OF IVAN IS LIKELY OCCURRING IN AN EVEN MORE SHEARED
   ENVIRONMENT AND ANY CELLS WITHIN THE BAND WILL CONTINUE TO POSE A
   THREAT OF TORNADOES.
   
   TORNADO POTENTIAL TO THE SOUTHWEST OF THE CENTER OF IVAN....
   INCLUDING MOBILE, AL...APPEARS TO BE LESSENING AS THE CYCLONE MOVES
   AWAY. SOME OF THESE AREAS WILL BE CLEARED FROM TORNADO WATCH 826
   SHORTLY.
   
   ..CARBIN.. 09/16/2004
   
   
   ATTN...WFO...TBW...JAX...FFC...TAE...BMX...MOB...
   
   29498263 30218819 33408825 32688370 31988369 31878263