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TROPICAL DEPRESSION FOUR-E DISCUSSION NUMBER   5
NATIONAL WEATHER SERVICE MIAMI FL
8 AM PDT WED JUL 10 2002
 
DEEP CONVECTION HAS REDEVELOPED NEAR THE CENTER OF TROPICAL 
DEPRESSION FOUR-E AND A 10/1019Z TRMM OVERPASS INDICATED GOOD 
BANDING FEATURES AND A TIGHT LOW-LEVEL CIRCULATION. AS SUCH...THE 
INITIAL INTENSITY IS INCREASED TO 30 KT AND THIS IS SUPPORTED BY A 
BLEND OF SATELLITE INTENSITY ESTIMATES OF 30 KT...35 KT...AND 25 KT 
FROM TAFB...SAB...AND AFWA...RESPECTIVELY. A RECENT 1300Z QUIKSCAT 
OVERPASS ALSO INDICATES THAT THERE IS INDEED A CLOSED CIRCULATION.
 
THE INITIAL MOTION ESTIMATE IS 280/15. THE INITIAL POSITION ESTIMATE 
IS SOMEWHAT UNCERTAIN...BUT THE 1019Z TRMM OVERPASS SUGGESTS THAT 
THE CENTER WAS RIGHT ON THE PREVIOUS FORECAST TRACK. AS SUCH...THE 
INITIAL POSITION AND MOTION ESTIMATE IS BASED MAINLY ON CONTINUITY 
WITH THE PREVIOUS FORECAST. HAVING SAID THAT...THERE REMAINS GOOD 
CONVERGENCE OF ALL NHC MODEL GUIDANCE OF A GENERAL WEST MOTION 
THROUGH 36 HOURS. AFTER THAT...THE AVN AND AVN 10-MEMBER ENSEMBLE 
AVERAGE MODELS SUGGEST THAT THE CYCLONE WILL TRACK MORE TOWARD THE 
WEST-NORTHWEST...WHICH IS ALSO CONSISTENT WITH THE NEW GFDL MODEL.  
THE NOGAPS AND UKMET MODELS ARE THE FARTHEST TO THE RIGHT AND TAKE 
THE SYSTEM NORTHWESTWARD AFTER 36 HOURS. THE AVN MODEL HAS DONE A 
GOOD JOB SO FAR WITH INTERACTION BETWEEN TD 4-E AND THE DISTURBANCE 
TO ITS SOUTHWEST. HOWEVER...THE LATTER FEATURE APPEARS TO HAVE 
DISSIPATED AND/OR BEEN ABSORBED BY THE DEPRESSION...SO THE SHARP 
WEST-SOUTHWESTWARD MOTION THAT THE EARLIER AVN AND GFDL MODELS HAVE 
BEEN FORECASTING IS LESS LIKELY TO OCCUR. AS A RESULT...THE OFFICIAL 
FORECAST IS A LITTLE TO THE RIGHT OF THE PREVIOUS TRACK AND IS CLOSE 
TO THE NEW AVN...AVN ENSEMBLE...AND GFDL MODEL CONSENSUS... 
ESPECIALLY GIVEN THE STRONG SUBTROPICAL RIDGE TO THE NORTH.
 
DURING THE PAST 4 HOURS...CIRRUS HAS BEEN EXPANDING WESTWARD ON THE 
WEST SIDE OF THE DEPRESSION WHICH SUGGESTS THAT THE WESTERLY SHEAR 
MAY BE STARTING TO WEAKEN. THIS WOULD ALLOW FOR SOME SIGNIFICANT 
STREGTHENING TO BEGIN IN 12 TO 24 HOURS...SO THE SHIPS AND GFDL 
INTENSITY TRENDS WERE FOLLOWED CLOSELY WITH EACH BRINGING THE 
CYCLONE UP TO 82 KT AND 91 KT IN 72 HOURS...RESPECTIVELY.
 
FORECASTER STEWART
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL     10/1500Z 13.3N 107.3W    30 KTS
12HR VT     11/0000Z 13.5N 109.3W    30 KTS
24HR VT     11/1200Z 13.7N 111.6W    35 KTS
36HR VT     12/0000Z 14.4N 113.7W    45 KTS
48HR VT     12/1200Z 15.0N 115.6W    60 KTS
72HR VT     13/1200Z 16.5N 118.5W    80 KTS
 
 
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