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TROPICAL DEPRESSION EIGHT DISCUSSION NUMBER   4
NATIONAL WEATHER SERVICE MIAMI FL
11 AM EDT WED SEP 12 2001

MORNING VISUAL IMAGES SHOW THAT THE SYSTEM HAS NOT CHANGED MUCH OVER 
THE PAST FEW HOURS.  THE BANDS OF DEEP CONVECTION STILL LACK 
CURVATURE...AND THE LOW-LEVEL CIRCULATION IS QUITE BROAD.  SURFACE 
OBSERVATIONS DO NOT SHOW STRONG WINDS...BUT 25 KNOTS WITH HIGHER 
GUSTS ARE CERTAINLY POSSIBLE IN THE CONVECTION TO THE EAST AND SOUTH 
OF THE CENTER.  WATER VAPOR IMAGERY SHOWS MORE NORTHERLY UPPER-LEVEL 
WINDS COMING TOWARD THE DEPRESSION...SO NOT MUCH STRENGTHENING IS 
LIKELY IN THE SHORT TERM.  HOWEVER...THE LATEST NCEP GLOBAL MODEL 
RUN INDICATES DECREASING SHEAR OVER THE AREA DURING THE NEXT DAY OR 
TWO...AND THE SHIPS GUIDANCE CALLS FOR INTENSIFICATION.  THE U.K. 
MET OFFICE MODEL ALSO SHOWS DEEPENING...BUT THIS MODEL MAY BE 
DEPICTING SOMETHING OTHER THAN A TRUE TROPICAL DEVELOPMENT.  THE 
OFFICIAL FORECAST SHOWS GRADUAL STRENGTHENING COMMENCING IN A DAY OR 
SO...AND IS JUST A LITTLE BELOW SHIPS.

MOTION ESTIMATE IS SLOWLY WEST...BUT THE CENTER IS ILL-DEFINED.  
STEERING IS WEAK...AND THERE MAY BE SOME ERRATIC MOTION OR CENTER 
REFORMATION DURING THE NEXT DAY OR SO.  THE AVN MODEL GRADUALLY 
DEVELOPS A POSITIVELY-TILTED 500 MB TROUGH ALONG THE U.S. EAST COAST 
NEAR THE END OF THE FORECAST PERIOD.  THIS FEATURE COULD TURN THE 
CYCLONE EASTWARD...AND THIS IS SHOWN IN THE OFFICIAL FORECAST.  
HOWEVER SOME OTHER GUIDANCE...SUCH AS THE NOGAPS AND U.K. MET 
MODEL...ARE FARTHER TO THE WEST OR SOUTHWEST.

FORECASTER PASCH
  
FORECAST POSITIONS AND MAX WINDS
 
INITIAL     12/1500Z 25.7N  85.9W    25 KTS
12HR VT     13/0000Z 25.8N  86.4W    30 KTS
24HR VT     13/1200Z 26.5N  87.0W    35 KTS
36HR VT     14/0000Z 27.5N  86.5W    40 KTS
48HR VT     14/1200Z 28.0N  85.5W    45 KTS
72HR VT     15/1200Z 28.5N  83.5W    60 KTS
 
 
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