[NCEP Logo] HOME ACTIVE
CYCLONES
FORECASTS IMAGERY ABOUT TPC RECONNAISSANCE

ZCZC MIATCDAT2 ALL
TTAA00 KNHC DDHHMM
TROPICAL DEPRESSION TWELVE DISCUSSION NUMBER   4
NATIONAL WEATHER SERVICE MIAMI FL
5 PM EDT WED OCT 06 1999
 
SATELLITE IMAGERY INDICATES THAT TROPICAL DEPRESSION TWELVE HAS
CHANGED LITTLE IN ORGANIZATION DURING THE DAY...WITH THE LOW LEVEL
CENTER EXPOSED TO THE WEST OF THE MAIN CONVECTION. SATELLITE
INTENSITY ESTIMATES FROM TAFB AND SAB REMAIN 35 KT AND 30 KT
RESPECTIVELY...AND THE INITIAL INTENSITY REMAINS AT 30 KT.
 
THE CENTER HAS SLOWED OR PERHAPS EVEN STALLED OVER THE PAST FEW
HOURS...BUT THIS IS BELIEVED TO BE A SHORT TERM CHANGE. THE INITIAL
MOTION FOR THIS PACKAGE IS 285/4...WHICH IS THE 24 HOUR MOTION.
THERE IS LITTLE CHANGE IN THE SYNOPTIC PATTERN OR THE MODEL GUIDANCE
FROM THE PREVIOUS PACKAGE. THE FORECAST TRACK CALLS FOR A GENERAL
WEST-NORTHWEST MOTION THROUGH THE FORECAST PERIOD...WITH PERHAPS A
LITTLE FASTER MOTION AFTER 24 TO 36 HOURS. IT IS ADJUSTED SLIGHTLY
TO THE EAST AND SLOWER ON THE BASIS OF THE CURRENT TRENDS.

THE CYCLONE CONTINUES TO HAVE A SHEARED APPEARANCE...AND WATER VAPOR
IMAGERY INDICATES THE AVN AND NOGAPS ARE TOO FAR NORTH AND NOT
STRONG ENOUGH WITH THE UPPER LEVEL TROUGH NORTH OF THE DEPRESSION. 
BOTH MODELS PREDICT THE TROUGH WILL WEAKEN AND MOVE AWAY...BUT THIS
WILL LIKELY BE A SLOWER PROCESS THAN THE MODELS FORECAST. THUS...THE
NEW INTENSITY FORECAST CALLS FOR SLOWER STRENGTHENING THAN THE
PREVIOUS PACKAGE.
 
BEVEN
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL     06/2100Z 15.5N  46.1W    30 KTS
12HR VT     07/0600Z 15.7N  46.6W    30 KTS
24HR VT     07/1800Z 16.1N  47.6W    35 KTS
36HR VT     08/0600Z 16.7N  48.7W    35 KTS
48HR VT     08/1800Z 17.5N  50.0W    40 KTS
72HR VT     09/1800Z 19.0N  52.5W    50 KTS
 
 
NNNN


Problems?