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TROPICAL DEPRESSION NINE-E DISCUSSION NUMBER   3
NATIONAL WEATHER SERVICE MIAMI FL
8 PM PDT TUE SEP 04 2001

TROPICAL DEPRESSION NINE-E GIVES THE IMPRESSION OF BEING SHEARED
THIS EVENING...WITH A CLUSTER OF STRONG CONVECTION TO THE WEST OF 
A PARTLY EXPOSED LOW LEVEL CENTER.  THERE MAY STILL BE SOME MID 
LEVEL CENTER FARTHER SOUTH IN THE CONVECTIVE CLOUD MASS.  ALTHOUGH
THE SATELLITE INTENSITY ESTIMATES FROM TAFB AND AFWA ARE 30 KT...
THE INITIAL INTENSITY WILL REMAIN 25 KT BASED ON A LESS IMPRESSIVE
OVERALL SATELLITE APPEARANCE THAN EARLIER TODAY.

THERE WAS A 60 NM SPREAD IN THE SATELLITE POSITIONS...SO THE
INITIAL MOTION IS A SOMEWHAT UNCERTAIN 295/14.  WATER VAPOR IMAGERY
INDICATES A MID/UPPER LEVEL ANTICYCLONE IS NORTH OF THE CYCLONE...
WHILE TROPICAL STORM GIL IS 750 NM TO THE WEST-SOUTHWEST MOVING
270/4.  THIS PATTERN WOULD GENERALLY SUPPORT A WEST-NORTHWEST OR
WESTWARD MOTION...AND THIS IS REFLECTED IN MOST OF THE NHC HURRICANE
GUIDANCE.  THE GREATEST POTENTIAL PROBLEM IN THIS FORECAST IS THE
POSSIBILITY OF THE DEPRESSION INTERACTING WITH GIL.  THE MOST LIKELY
RESULT OF SUCH AN INTERACTION ON NINE-E WOULD BE A FASTER MOTION
TO THE WEST-NORTHWEST OR WEST BETWEEN GIL AND THE RIDGE TO THE
NORTH.  THE OFFICIAL FORECAST WILL BE A LITTLE TO THE SOUTH OF THE
PREVIOUS FORECAST AND SOMEWHAT FASTER...REFLECTING THE CHANGE IN
THE INITIAL POSITION/MOTION AND THE POSSIBILITY OF INTERACTION WITH
GIL.
 
THE INTENSITY FORECAST IS ALSO TRICKY.  WHILE THE SYSTEM IS
CURRENTLY SHEARED FROM THE EAST OR NORTHEAST...THE -80C TOPS IN THE
MAIN CONVECTION SUGGEST THAT STRENGTHENING IS STILL POSSIBLE.  THE
SHIPS MODEL TAKES THE SYSTEM TO 50 KT IN 36 HR...WHILE THE GFDL
DISSIPATES THE CYCLONE IN 48 HR.  BOTH OF THE FORECASTS ARE
POSSIBLE...AND THUS A COMPROMISE IS PROBABLY IN ORDER.  THE
INTENSITY FORECAST WILL CALL FOR SLIGHTLY FASTER STRENGTHENING THAN
IN THE PREVIOUS PACKAGE...MAKING THE CYCLONE A STORM IN 36 HR.  BY
72 HR THE SYSTEM MAY MOVE INTO COOLER WATER AND START TO WEAKEN.
 
FORECASTER BEVEN
 
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL     05/0300Z 18.0N 112.2W    25 KTS
12HR VT     05/1200Z 18.7N 114.2W    30 KTS
24HR VT     06/0000Z 19.4N 116.4W    30 KTS
36HR VT     06/1200Z 20.0N 118.5W    35 KTS
48HR VT     07/0000Z 20.7N 120.6W    35 KTS
72HR VT     08/0000Z 22.0N 124.5W    30 KTS
 
 
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