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TROPICAL DEPRESSION ELEVEN-E DISCUSSION NUMBER   3
NATIONAL WEATHER SERVICE MIAMI FL
2 AM PDT FRI SEP 06 2002
 
TROPICAL DEPRESSION ELEVEN-E CONTINUES TO BECOME BETTER ORGANIZED.
A SMALL CDO-LIKE FEATURE HAS DEVELOPED OVER THE LOW-LEVEL CENTER
WHICH WOULD SUGGEST THAT THE CYCLONE IS AT OR NEAR TROPICAL STORM
STRENGTH.  THE INITIAL INTENSITY REMAINS 30 KT BASED ON A DVORAK
SATELLITE INTENSITY ESTIMATE OF 30 KT FROM BOTH TAFB AND SAB.
UPPER-LEVEL OUTFLOW IS GOOD TO THE SOUTH BUT ONLY FAIR TO THE NORTH.

THE INITIAL MOTION ESTIMATE IS 310/10.  THE NHC MODEL GUIDANCE...
EXCEPT FOR THE AVN MODEL...IS TIGHTLY CLUSTERED ABOUT A GENERAL
NORTHWESTWARD MOTION THROUGHOUT THE FORECAST PERIOD.  THE AVN
APPEARS TO BE AN OUTLIER AS IT UNCHARACTERISTICALLY TAKES THE
CYCLONE ALMOST DUE WEST FROM ITS CURRENT POSITION.  THIS MAY BE DUE
TO THE FACT THAT TD 11-E IS VERY SMALL AND THE AVN DOES NOT
STRENGTHEN IT ENOUGH TO EVEN PRODUCE A CLOSED STANDARD ISOBAR AROUND
THE SYSTEM.  THE AVN SOLUTION WAS DISCOUNTED GIVEN THE CURRENT
STEADY NORTHWEST MOTION OF 8 TO 10 KT AND THE STRONG SUBTROPICAL
RIDGE TO THE NORTH AND EAST WHICH SHOULD KEEP THE DEPRESSION MOVING
IN A GENERAL NORTHWESTWARD DIRECTION.  THE OFFICIAL FORECAST TRACK
IS JUST A TAD TO THE EAST OF THE PREVIOUS FORECAST AND IS BETWEEN
THE GFDL AND UKMET-NOGAPS MODELS.  HOWEVER...IT SHOULD BE NOTED THAT
THE GFDL IS THE RIGHTMOST AND SLOWEST OF ALL THE MODELS AND IT
BRINGS THE CENTER VERY CLOSE TO CABO SAN LAZARO IN 36 TO 48 HOURS.

THE INTENSITY FORECAST WAS INCREASED SLIGHTLY GIVEN THE SMALL SIZE
OF THE DEPRESSION AND THE FACT THAT IT OVER 29C SSTS.  A SMALL CDO 
HAS ALREADY FORMED OVER THE CENTER AND A 06/0406Z TRMM OVERPASS 
INDICATED A WELL-DEFINED 10 NMI DIAMETER MID- AND UPPER-LEVEL 
CIRCULATION THAT CLOSELY RESEMBLES AN EYE FEATURE. THE ONLY THING 
THAT PRECLUDES FORECASTING RAPID INTENSIFICATION IS THE PRESENCE OF 
DRY AIR SEEN IN WATER VAPOR IMAGERY WHICH IS LOCATED ABOUT 150 NMI 
WEST OF THE CENTER. DUE TO THE UNCERTAINTY ABOUT WHETHER OR NOT THE 
DRY AIR WILL GET ENTRAINED INTO THE SYSTEM...I HAVE KEPT THE 
INTENSIFICATION TREND ON THE CONSERVATIVE SIDE.  HOWEVER...THE 
OFFICIAL FORECAST IS STILL HIGHER THAN THE SHIPS MODEL AT 24 AND 36 
HOURS...AND ALSO AT 72 HOURS. THE LACK OF SIGNIFICANT STREGTHENING 
BY THE SHIPS INTENSITY MODEL IS SOMEWHAT PUZZLING GIVEN THAT THE 
CYCLONE IS FORECAST TO REMAIN OVER 26C OR HIGHER SSTS AND UNDER LESS 
THAN 10 KT OF VERTICAL SHEAR THROUGH 36 HOURS.

DUE TO THE CLOSE PROXIMITY OF THE FORECAST TRACK TO BAJA CALIFORNIA 
AND THE POSSIBILITY OF THIS SYSTEM REACHING MINIMAL HURRICANE 
STRENGTH...THE GOVERNMENT OF MEXICO HAS REPLACED THE TROPICAL STORM 
WATCH WITH A TROPICAL STORM WARNING AND A HURRICANE WATCH FROM CABO 
SAN LUCAS NORTHWARD TO CABO SAN LAZARO.
 
FORECASTER STEWART
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL     06/0900Z 20.5N 109.1W    30 KTS
12HR VT     06/1800Z 21.3N 110.1W    40 KTS
24HR VT     07/0600Z 22.6N 111.5W    50 KTS
36HR VT     07/1800Z 23.8N 112.7W    60 KTS
48HR VT     08/0600Z 25.2N 113.7W    55 KTS
72HR VT     09/0600Z 28.0N 115.5W    40 KTS
 
 
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