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TROPICAL STORM ALETTA DISCUSSION NUMBER   6
NATIONAL WEATHER SERVICE MIAMI FL
2 PM PDT TUE MAY 23 2000
 
HIGH RESOLUTION VISIBLE SATELLITE LOOPS INDICATE THAT THE CENTER OF
ALETTA EITHER REFORMED SOUTH OF THE PREVIOUS LOCATION WITHIN THE
DEEP CONVECTION OR MOVED SOUTH OF DUE WEST.  THE INITIAL POSITION
HAS BEEN SLIGHTLY ADJUSTED SOUTHWESTWARD ACCORDINGLY. 

THE CLOUD PATTERN CONTINUES TO IMPROVE IN ORGANIZATION WITH A
CONVECTIVE BAND WRAPPING A PORTION OF THE TROPICAL CYCLONE AND AN
AREA OF DEEP CONVECTION NEAR THE CENTER.  T-NUMBERS HAVE INCREASED
TO 3.0 ON THE DVORAK SCALE...EQUIVALENT TO 45-KNOT WINDS.  ALTHOUGH
THE SHIPS MODEL STRENGTHENS ALETTA TO 75 KNOTS MAINLY DUE TO WARM
WATERS...THE GFDL...UK AND AVN MODELS SUGGEST WEAKENING BY THE END
OF THE FORECAST PERIOD AS THE CIRCULATION BECOMES ABSORBED BY A
TROUGH OR BECOMES ILL DEFINED.  THE OFFICIAL FORECAST CONTINUES TO
SHOW A GRADUAL STRENGTHENING BUT NOT AS MUCH AS SHIPS.

GLOBAL MODELS INSIST ON WEAKENING THE STEERING CURRENTS BEYOND 36
HOURS. THIS WOULD RESULT IN LITTLE MOTION OF THE TROPICAL CYCLONE. 
THE OFFICIAL FORECAST KEEPS ALETTA ON A GENERAL AND SLOW WESTWARD
TRACK BUT WITH A MARKED DECREASE IN FORWARD SPEED BY THE END OF THE
FORECAST PERIOD.  THIS IS BASED ON THE FACT THAT IT IS HARD TO
IGNORE THE AVN...UK AND GFDL MODELS.

FORECASTER AVILA
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL     23/2100Z 14.5N 103.4W    45 KTS
12HR VT     24/0600Z 14.7N 104.2W    45 KTS
24HR VT     24/1800Z 14.9N 105.0W    50 KTS
36HR VT     25/0600Z 15.0N 105.5W    55 KTS
48HR VT     25/1800Z 15.0N 106.0W    60 KTS
72HR VT     26/1800Z 15.5N 107.0W    60 KTS
 
 
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