Tropical Depression SIX

ZCZC MIATCDAT1 ALL
TTAA00 KNHC DDHHMM
TROPICAL DEPRESSION SIX DISCUSSION NUMBER   5
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
5 PM EDT SUN JUL 20 2003
 
THE INITIAL MOTION ESTIMATE IS 275/20.  THE GFS SHOWS AN INCREASING
WEAKNESS IN THE SUBTROPICAL RIDGE IN THE GULF OF MEXICO OVER THE
NEXT SEVERAL DAYS AND THIS IS EXPECTED TO INCREASE THE NORTHWARD
COMPONENT OF MOTION.  THE UKMET AND NOGAPS ARE THE ONLY DYNAMICAL
MODELS TO HOLD ON TO A CIRCULATION FOR FIVE DAYS AND THESE MODELS
SHOW A FIVE DAY POSITION NEAR CENTRAL FLORIDA.  THE GFS AND GFDL
ARE FURTHER SOUTH BUT ONLY CARRY A CIRCULATION FOR 36 HOURS.  THE
OFFICIAL FORECAST IS A BLEND OF THE GUIDANCE AND CONSIDERABLY SOUTH
OF THE UKMET AND NOGAPS.  THIS UNCERTAINTY AFTER 72 HOURS IS A
LITTLE MORE THAN WE HAVE SEEN IN RECENT PAST STORMS.
 
THERE HAS BEEN A RECENT INCREASE IN DEEP CONVECTION...BUT VISIBLE
IMAGERY STILL DOES NOT SHOW A WELL DEFINED LOW LEVEL CIRCULATION
AND THE INITIAL WIND SPEED REMAINS 30 KNOTS.  NONE OF THE
GUIDANCE...EXCEPT FOR THE PURE STATISTICAL...BRINGS THE WINDS TO
HURRICANE FORCE DURING THE NEXT FIVE DAYS.  THEREFORE THE OFFICIAL
FORECAST IS TO 60 KNOTS BY DAY FOUR AND FIVE...BACKING OFF A LITTLE
FROM THE PREVIOUS ADVISORY.
 
IF THE DEPRESSION BECOMES A STORM AS FORECAST...TROPICAL STORM
CONDITIONS SHOULD REACH THE CENTRAL ISLANDS OF THE LESSER ANTILLES
IN ABOUT 24 HOURS.  BUT SINCE THE SYSTEM REMAINS RATHER
UNIMPRESSIVE...A TROPICAL STORM WATCH IS POSTED FOR ST LUCIA AND
DOMINICA.  THE FRENCH ISLANDS CHOOSE TO WAIT A WHILE LONGER.
 
FORECASTER LAWRENCE
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      20/2100Z 13.3N  52.6W    30 KT
 12HR VT     21/0600Z 13.9N  55.8W    35 KT
 24HR VT     21/1800Z 14.5N  59.8W    40 KT
 36HR VT     22/0600Z 15.5N  63.9W    45 KT
 48HR VT     22/1800Z 16.6N  67.7W    50 KT
 72HR VT     23/1800Z 19.0N  75.0W    55 KT
 96HR VT     24/1800Z 21.5N  80.5W    60 KT
120HR VT     25/1800Z 24.0N  85.0W    60 KT
 
 
NNNN