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TROPICAL STORM LILI DISCUSSION NUMBER  11
NATIONAL WEATHER SERVICE MIAMI FL
11 PM EDT MON SEP 23 2002
 
THE SHEARED CONVECTIVE PATTERN HAS CHANGED LITTLE DURING THE PAST
SEVERAL HOURS...WITH THE LOW LEVEL CENTER CONTINUING TO ADVANCE
WEST AND AHEAD OF THE MID LEVEL CLOUD CIRCULATION CENTER.  DVORAK
SATELLITE INTENSITY ESTIMATES REMAIN 45 KNOTS FROM ALL
AGENCIES...AND AN AIR FORCE RECONNAISSANCE AIRCRAFT RECENTLY
REPORTED FLIGHT LEVEL WINDS OF 45 KNOTS...EQUATING ROUGHLY TO 35
KNOTS AT THE SURFACE...TO THE NORTHWEST OF THE CENTER.
HOWEVER...THE INITIAL INTENSITY REMAINS 50 KNOTS SINCE THE AIRCRAFT
HAS YET TO SAMPLE THE NORTHEASTERN QUADRANT WHERE MOST OF THE
CONVECTION IS LOCATED.  THE MINIMUM CENTRAL PRESSURE HAS BEEN
ADJUSTED TO 1006 MB BASED UPON AIRCRAFT RECONNAISSANCE AND SURFACE
OBSERVATIONS.

THE INITIAL MOTION REMAINS WESTWARD...275/15.  ALL OF THE GLOBAL
MODELS CONTINUE TO INSIST ON A MORE POLEWARD MOTION...DUE TO A
WEAKNESS IN THE SUBTROPICAL RIDGE TO THE NORTH...THAT WOULD TAKE
THE SYSTEM OVER THE DOMINICAN REPUBLIC IN ABOUT 72 HOURS.  GIVEN
THE CURRENT WESTWARD MOTION...THE OFFICIAL FORECAST REMAINS
SLIGHTLY TO THE LEFT OF THE GLOBAL MODELS BUT TO THE RIGHT OF THE
PREVIOUS ADVISORY TRACK...AND IS MORE CONSERVATIVE THAN THE MODELS
REGARDING A TURN TO THE RIGHT BEYOND 48 HOURS.

THE INTENSITY FORECAST REASONING REMAINS ESSENTIALLY UNCHANGED.
THE MID TO UPPER LEVEL LOW CURRENTLY OVER VENEZUELA IS FORECAST TO
MOVE TO THE SOUTHWEST...AND AN UPPER LEVEL ANTICYCLONE SHOULD THEN
DEVELOP OVER THE EASTERN CARIBBEAN AND REDUCE THE SHEAR IMPACTING
THE SYSTEM...AND THE SLOWER SPEED OF THE SYSTEM SHOULD ALLOW THE
CONVECTION AND LOW LEVEL CENTER TO BE SUPERIMPOSED.  THE OFFICIAL
FORECAST CLOSELY FOLLOWS THE SHIPS MODEL...EXCEPT AT 72 HOURS WHEN
THE TROPICAL CYCLONE MAY BE SOMEWHAT DISRUPTED BY THE TERRAIN OF
HISPANIOLA.

FORECASTER JARVINEN/KNABB
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL     24/0300Z 12.7N  62.7W    50 KTS
12HR VT     24/1200Z 13.8N  64.8W    55 KTS
24HR VT     25/0000Z 15.0N  67.1W    60 KTS
36HR VT     25/1200Z 16.1N  69.0W    70 KTS
48HR VT     26/0000Z 17.0N  70.5W    75 KTS
72HR VT     27/0000Z 19.0N  73.0W    70 KTS...NEAR HAITI
 
 
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