000
WTNT43 KNHC 031442
TCDAT3
TROPICAL STORM FIONA DISCUSSION NUMBER  16
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL082010
1100 AM AST FRI SEP 03 2010
 
AIRCRAFT DATA FROM THIS MORNING SHOWED PEAK SFMR WINDS OF 39 KT AND
FLIGHT-LEVEL WINDS OF 48 KT...SUPPORTING AN INITIAL WIND SPEED OF
ABOUT 40 KT. SATELLITE IMAGES SHOW THAT CONVECTION HAS BECOME
RATHER THIN NEAR THE CENTER...WITH THE CIRCULATION OF FIONA ALSO
TAKING ON AN ELONGATED APPEARANCE. SLOW WEAKENING SEEMS LIKELY
GIVEN THE PERSISTENT NORTHERLY SHEAR AND MODEL GUIDANCE IS ON GOOD
AGREEMENT WITH THIS SCENARIO. THE NHC FORECAST IS BASICALLY AN
UPDATE OF THE PREVIOUS ADVISORY. ALL MODELS WEAKEN THE SYSTEM
DRAMATICALLY IN A COUPLE OF DAYS...AND DISSIPATION IS EXPECTED
AFTER THAT TIME. GIVEN THE LATEST SATELLITE PRESENTATION...IT WOULD
NOT BE A SURPRISE IF FIONA DECAYED FASTER THAN THE FORECAST BELOW.

FIONA HAS TURNED TO THE NORTH-NORTHEAST AND IS MOVING 020/11 KT. THE
MODELS ARE WELL CLUSTERED NOW ON BRINGING THE CENTER NEAR BERMUDA
IN ABOUT 18 HOURS. THEREAFTER...SOME ACCELERATION IS ANTICIPATED AS
THE STORM ENCOUNTERS INCREASING SOUTHWESTERLY FLOW. THE NHC
FORECAST IS VERY CLOSE TO THE PREVIOUS ONE AND THE DYNAMICAL MODEL
CONSENSUS.

THE INITIAL WIND RADII HAVE BEEN REDUCED BASED ON AIRCRAFT
DATA...AND STILL MIGHT BE A LITTLE GENEROUS.  

 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      03/1500Z 29.0N  66.4W    40 KT
 12HR VT     04/0000Z 30.6N  65.7W    35 KT
 24HR VT     04/1200Z 32.7N  64.6W    35 KT
 36HR VT     05/0000Z 35.2N  63.1W    30 KT
 48HR VT     05/1200Z 38.1N  61.2W    25 KT
 72HR VT     06/1200Z...DISSIPATED
 
$$
FORECASTER BLAKE