MESOSCALE DISCUSSION 0047
   NWS STORM PREDICTION CENTER NORMAN OK
   0631 PM CST MON JAN 26 2004
   
   AREAS AFFECTED...NRN FL...N CNTRL FL PEN
   
   CONCERNING...CONVECTIVE TRENDS 
   
   VALID 270031Z - 270300Z
   
   NEW WW IS NOT CURRENTLY ANTICIPATED.
   
   WEAK SHORT WAVE TROUGH EMBEDDED WITHIN SUBTROPICAL MID/UPPER MOIST
   PLUME NOW APPEARS TO BE SHIFTING NORTHEASTWARD OFF THE SOUTH
   ATLANTIC COASTAL AREAS.  HOWEVER...MID-LEVEL SHEAR AXIS TRAILS TO
   THE SOUTHWEST ACROSS NORTHERN FLORIDA...TO THE WEST OF
   JACKSONVILLE...INTO THE NORTHEASTERN GULF OF MEXICO.  THIS FEATURE
   IS PROVIDING FORCING/FOCUS FOR NARROW LEADING CONVECTIVE BAND ACROSS
   NORTHERN FLORIDA...WHICH IS CURRENTLY MOST ACTIVE WITH REGARD TO
   CLOUD TO GROUND LIGHTNING STRIKES.
   
   ISENTROPIC ASCENT/LIFT OF MOIST...POTENTIALLY UNSTABLE PARCELS OFF
   THE NORTHEASTERN GULF OF MEXICO...ALONG 40 KT SOUTH SOUTHWESTERLY
   LOW-LEVEL JET.... IS PROVIDING LOW-LEVEL FORCING FOR THUNDERSTORM
   ACTIVITY.  ALTHOUGH CONVECTION APPEARS CURRENTLY ROOTED ABOVE
   BOUNDARY LAYER...OBJECTIVE ANALYSIS/MODEL FORECAST SOUNDINGS AND
   LATEST RAOB DATA SUGGEST AIR MASS TO THE IMMEDIATE SOUTH/WEST OF
   JACKSONVILLE STILL POSSESSES WEAK TO MODERATE SURFACE-BASED
   INSTABILITY.
   
   MEAN MIXED LAYER CAPE EXCEEDS 1000 J/KG...BUT WEAK MID-LEVEL LAPSE
   RATES APPEARS LIKELY TO CONTINUE TO MINIMIZE HAIL THREAT.  VEERED
   LOW-LEVEL FLOW IS NOW MINIMIZING SIZE AND CLOCKWISE CURVATURE OF
   LOW-LEVEL HODOGRAPHS WHICH SHOULD LIMIT TORNADO THREAT.  AN ISOLATED
   DAMAGING WIND GUST...HOWEVER...STILL APPEARS POSSIBLE WITH
   UNSATURATED MID-LEVEL AIR MASS ENHANCING EVAPORATIVE COOLING IN
   DOWNDRAFTS...AND POTENTIAL FOR DOWNWARD TRANSFER OF HIGHER MOMENTUM
   AIR ASSOCIATED WITH LOW-LEVEL JET.
   
   WITH PRIMARY UPPER TROUGH STILL UPSTREAM...LINE WILL BE SLOW TO
   PROGRESS EASTWARD ACROSS NORTHERN FLORIDA AND THE NORTHERN FLORIDA
   PENINSULA...AND MAY NOT PROGRESS EAST OF JACKSONVILLE FOR ANOTHER
   SEVERAL HOURS.
   
   ..KERR.. 01/27/2004
   
   
   ATTN...WFO...JAX...TAE...MLB...TBW...
   
   29548338 29968292 30368237 30568186 30758148 
   
   29888115 29418164 28978187 28448259