HOME	ACTIVE CYCLONES	FORECASTS	IMAGERY	ABOUT TPC	RECONNAISSANCE

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TROPICAL STORM LENNY DISCUSSION NUMBER  31
NATIONAL WEATHER SERVICE MIAMI FL
10 PM EST SAT NOV 20 1999
 
THE CENTER IS DIFFICULT TO LOCATE ON SATELLITE IMAGERY.  USING
ISLAND...SHIP AND BUOY REPORTS...AND CONTINUITY...GIVES AN INITIAL
MOTION OF 125/07...BUT THIS IS HIGHLY UNCERTAIN AND THERE MAY NO
LONGER BE A WELL DEFINED LOW LEVEL CIRCULATION.  THE GUIDANCE MODELS
SHOW A MOSTLY NORTHEASTWARD MOTION THROUGH 72 HOURS.  USING THE
INITIAL MOTION FOR THE FIRST 12 HOURS OF THE FORECAST MOVES THE
TRACK WELL TO THE RIGHT OF THE PREVIOUS ADVISORY.   ALSO THE
FORECAST TRACK IS A LITTLE SLOWER TO ACCOUNT FOR THE UNCERTAINTY IN
LOCATION AND MOTION AND FOR THE PERSISTANT NORTH BIAS THAT ALL OF
THE GLOBAL MODELS HAVE DISPLAYED DURING THE PAST SEVERAL DAYS. 
MAYBE NUMERICAL MODELS ARE NOT ABLE TO MOVE A SLOW MOVING TROPICAL
CYCLONE SOUTHWARD IN THE DEEP TROPICS??
 
AN AREA OF DEEP CONVECTION CONTINUES NEAR AND EAST OF THE ESTIMATED
LOW LEVEL CENTER LOCATION.  DVORAK INTENSITIES RANGE FROM 30 TO 55
KNOTS BUT THE SHIPS AND BUOYS HAVE NOT REPORTED A WIND SPEED AS
HIGH AS 35 KNOTS SINCE 12Z.  SO THE WIND IS REDUCED TO 40 KNOTS AND
CONTINUED SLOW WEAKENING IS FORECAST.
 
LAWRENCE
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL     21/0300Z 15.5N  58.9W    40 KTS
12HR VT     21/1200Z 15.1N  57.7W    35 KTS
24HR VT     22/0000Z 15.6N  56.1W    35 KTS
36HR VT     22/1200Z 16.8N  54.8W    30 KTS
48HR VT     23/0000Z 18.3N  53.2W    30 KTS
72HR VT     24/0000Z 22.0N  50.5W    30 KTS
  
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