Tropical Depression ONE

ZCZC MIATCDAT1 ALL
TTAA00 KNHC DDHHMM
TROPICAL DEPRESSION ONE DISCUSSION NUMBER   5
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL012006
500 AM EDT SUN JUN 11 2006
 
QUIKSCAT DATA...NIGHT-VIS SATELLITE IMAGERY...AND A SHIP REPORT FROM
WCY8453 INDICATE THAT THE CENTER OF THE DEPRESSION IS A LITTLE WEST
OF OUR PREVIOUS TRACK...INDEED PROBABLY FARTHER WEST THAN THE
CURRENT ADVISORY POSITION...AND INCREASINGLY REMOVED FROM THE DEEP
CONVECTION.  NEVERTHELESS...THE PULASKI SHOAL LIGHT CMAN
STATION...NEAR THE DRY TORTUGAS...REPORTED A 10-MINUTE MEAN WIND OF
36 KT SHORTLY BEFORE 06Z IN A NARROW BAND OF CONVECTION THAT HAS
SINCE DISSIPATED.  IT IS QUITE POSSIBLE THAT THERE ARE STILL A FEW
SPOTS OF TROPICAL STORM FORCE WINDS AROUND...BUT I AM LOATH TO
UPGRADE THE DEPRESSION GIVEN THE SATELLITE PRESENTATION AND THE
RECENT CONVECTIVE TRENDS.
 
THE INITIAL MOTION ESTIMATE IS 325/8.  THE DEPRESSION IS SOUTH OF A
MID-LEVEL RIDGE OVER THE NORTHERN GULF THAT EXTENDS EASTWARD INTO
THE WESTERN ATLANTIC...WHILE STRONG SOUTHWESTERLY FLOW CONTINUES
OVER THE CYCLONE CENTER.  THIS SHEARING FLOW LEADS TO TWO VERY
DIFFERENT FORECAST SCENARIOS.  THE GFS...NOGAPS...CANADIAN...AND
GFDL MODELS MAINTAIN OR STRENGTHEN THE DEPRESSION AND LIFT IT
NORTHEASTWARD WITH A MID-LATITUDE TROUGH IN 36-48 HOURS.  THIS IS
THE SCENARIO THAT THE LAST FEW OFFICIAL FORECASTS HAVE FOLLOWED...
AND WHICH I WILL MAINTAIN FOR THIS ADVISORY PACKAGE.  HOWEVER...A
SECOND SCENARIO IS BECOMING INCREASINGLY LIKELY...IN WHICH THE
DEPRESSION IS SEPARATED FROM ITS DEEP CONVECTION BY THE
SOUTHWESTERLY SHEAR...LEAVING A WEAK VORTEX TO LINGER AND
DEGENERATE IN THE WESTERN GULF OF MEXICO.  IF DAYLIGHT IMAGERY
AND/OR RECONNAISSANCE DATA CONFIRM THAT THE WESTERN CENTER IS THE
ONLY CENTER...THEN SOME SIGNIFICANT ADJUSTMENTS IN THE TRACK AND
INTENSITY FORECASTS WILL LIKELY BE NECESSARY LATER TODAY.
 
 
FORECASTER FRANKLIN
 
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      11/0900Z 23.5N  87.0W    30 KT
 12HR VT     11/1800Z 24.7N  87.4W    35 KT
 24HR VT     12/0600Z 26.0N  87.0W    35 KT
 36HR VT     12/1800Z 27.5N  85.3W    40 KT
 48HR VT     13/0600Z 29.2N  83.0W    40 KT
 72HR VT     14/0600Z 32.0N  77.0W    40 KT...EXTRATROPICAL
 96HR VT     15/0600Z 39.0N  68.0W    40 KT...EXTRATROPICAL
120HR VT     16/0600Z 46.0N  56.0W    40 KT...EXTRATROPICAL
 
 
$$
NNNN