MESOSCALE DISCUSSION 2262
   NWS STORM PREDICTION CENTER NORMAN OK
   1013 AM CDT SUN SEP 26 2004
   
   AREAS AFFECTED...PORTIONS ERN/NRN FL...SERN GA
   
   CONCERNING...TORNADO WATCH 840...
   
   VALID 261513Z - 261715Z
   
   AS SFC HEATING CONTINUES AROUND PERIPHERY OF CYCLONE THROUGHOUT
   DAYLIGHT HOURS...BOUNDARY LAYER WILL BECOME MORE BUOYANT AND SOME OF
   THIS AIR SHOULD BE DRAWN INTO NERN PORTION OF JEANNE.  THEREFORE
   EXPECT OVERALL SUPERCELL POTENTIAL TO INCREASE.  THIS INCLUDES AIR
   MASS NOW OVER SERN GA...WHERE MOIST ADVECTION IS EXPECTED WITH
   INCREASING ELY/DECREASING NLY FLOW COMPONENT...AND WHERE LOW LEVEL
   SHEAR WILL INCREASE GRADUALLY WITH TIME.
   
   IN NEAR TERM AN AREA OF MAXIMIZED RISK IS EVIDENT -- ACROSS PORTIONS
   VOLUSIA/FLAGLER/ST. JOHNS COUNTIES THROUGH AT LEAST 17Z...SPREADING
   OVER CLAY/PUTNAM/DUVAL/ALACHUA/UNION/BRADFORD/ BAKER COUNTIES
   THROUGH 18Z AND BEYOND.  AS OF 15Z CENTER OF JEANNE IS OVER POLK
   COUNTY.  SFC ANALYSIS SHOWS PRONOUNCED SFC TROUGH/WIND SHIFT LINE
   EXTENDING FROM THERE ENEWD OVER CAPE CANAVERAL TO POSITION
   APPROXIMATELY 30 NM N OF BUOY 41010 IN ATLANTIC.  EXPECT THIS TROUGH
   TO SHIFT NWWD IN STEP WITH CENTER OF TROPICAL CYCLONE. DRYING
   EVIDENT IN REFLECTIVITY/SATELLITE LOOPS AND PERIPHERAL 12Z RAOBS IS
   EXPECTED TO WRAP INTO MORE OF ERN SEMICIRCLE OF CIRCULATION...AIDING
   IN DIURNAL HEATING.  TROUGH THEN MAY BECOME WEAK BAROCLINIC
   ZONE...AND IN ANY EVENT SHOULD ENHANCE TORNADO POTENTIAL BOTH
   1. WHERE IT INTERSECTS OUTER BAND NOW EXTENDING SEWD FROM DAB AND
   2. WHERE ANY DISCRETE CELLS ON EITHER SIDE OF BAND MAY CROSS IT.
   
   REF LATEST NHC ADVISORIES -- I.E. WMO HEADER WTNT21 KNHC -- FOR
   LATEST TROPICAL WATCHES/WARNINGS AND TRACK/INTENSITY GUIDANCE ON
   JEANNE.
   
   ..EDWARDS.. 09/26/2004
   
   
   ATTN...WFO...CHS...MLB...TBW...JAX...TAE...
   
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