HOME	ACTIVE CYCLONES	FORECASTS	IMAGERY	ABOUT TPC	RECONNAISSANCE

ZCZC MIATCDAT1 ALL
TTAA00 KNHC DDHHMM
HURRICANE LENNY DISCUSSION NUMBER  10
NATIONAL WEATHER SERVICE MIAMI FL
4 PM EST MON NOV 15 1999
 
BASED ON A RECENT AIRCRAFT FIX...THE INITIAL MOTION IS 095/13.  THIS
IS A LITLE FASTER THAN BEFORE AND THE SATELLITE FIXES GIVE A MOTION
CLOSER TO 10 KNOTS.  THE REASONING FOR THE FORECAST TRACK IS
UNCHANGED.  A DEEPENING TROUGH OVER THE WESTERN NORTH ATLANTIC IS
EXPECTED TO MOVE THE HURRICANE MOSTLY EASTWARD AND THEN
NORTHEASTWARD FOR THE NEXT 72 HOURS.  SOME OF THE GUIDANCE INDICATES
THAT THE FORWARD MOTION MAY SLOW A LITTLE AFTER 48 HOURS AS THE
SHORT WAVE MOVES AWAY WITHOUT TOTALLY PICKING UP THE HURRICANE.  THE
OFFICIAL FORECAST IS THEREFORE A LITTLE SLOWER THAN THE PREVIOUS
ADVISORY AFTER 48 HOURS...OTHERWISE THERE IS LITTLE CHANGE TO THE
TRACK FORECAST.
 
THE CENTRAL PRESSURE HAS RISEN FROM 971 TO 981 IN 12 HOURS AND THE
MAXIMUM WIND MEASURED BY RECON IS 73 KNOTS FROM A GPS DROP IN THE
SOUTHWEST QUADRANT.  THE WIND SPEED IS DECREASED TO 75 KNOTS ON THIS
BASIS.  THE SHIPS MODEL FORECASTS 15 KNOTS OF STRENGTHENING IN
36 HOURS.  BUT BECAUSE OF THE CURRENT WEAKENING TREND...THE WIND
SPEED WILL BE HELD CONSTANT AT 75 KNOTS THROUGH 72 HOURS.
 
BASED ON THE FORECAST TRACK...IT IS NOW TIME TO ISSUE A HURRICANE
WATCH FOR PUERTO RICO AND THE U.S. AND BRITISH VIRGIN ISLANDS.
 
LAWRENCE
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL     15/2100Z 14.9N  74.1W    75 KTS
12HR VT     16/0600Z 14.9N  72.2W    75 KTS
24HR VT     16/1800Z 15.7N  69.9W    75 KTS
36HR VT     17/0600Z 17.0N  68.0W    75 KTS
48HR VT     17/1800Z 18.5N  66.0W    75 KTS
72HR VT     18/1800Z 20.5N  63.5W    75 KTS
  
NNNN