Tropical Storm ANA

ZCZC MIATCDAT1 ALL
TTAA00 KNHC DDHHMM
TROPICAL STORM ANA DISCUSSION NUMBER   7
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
11 AM EDT TUE APR 22 2003
 
AT 09Z...A SHIP REPORTED 44 KT AT A POSITION ABOUT 50 N MI SOUTH OF
THE CENTER AND THE INITIAL WIND SPEED IS INCREASED TO 45 KT FOR THIS
ADVISORY.  BASED ON THE PROXIMITY OF THE STRONGEST WINDS TO THE
CENTER OF THE CYCLONE AS WELL AS AMSU TEMPERATURE STRUCTURE DATA
WHICH SHOWS A SLIGHTLY WARM CORE NEAR THE SURFACE AND ALOFT...ANA IS
CHANGED FROM SUBTROPICAL TO TROPICAL STATUS.

CIMSS CLOUD MOTION VERTICAL WIND SHEAR IS ABOUT 30 KT OVER ANA AND
GUIDANCE MODELS SHOW THIS SHEAR PERSISTING THROUGH 72 HOURS.  WILL
THE PRESENT SHEAR KILL THE STORM?  THE SHIPS MODEL AND UKMET SHOW
DISSIPATION BY 72 HOURS WHILE THE GFS AND GFDL MODELS MAINTAIN A 40
TO 50 KT CIRCULATION THROUGH 72 HOURS.  THE OFFICIAL FORECAST
MAINTAINS THE CYCLONE WITH SOME WEAKENING THROUGH 72 HOURS.

THE INITIAL MOTION IS 080/14.  ANA IS EMBEDDED IN A WESTERLY CURRENT
AND IS FORECAST TO MOVE EAST TO EAST-NORTHEASTWARD FOR 72 HOURS IN
GENERAL AGREEMENT WITH THE GFS...GFDL...AND NOGAPS MODELS.  THE
UKMET MODEL SHOWS A STRANGE TURN TOWARD THE SOUTH...THEN
DISSIPATION...IN 48 HOURS.

THE 34-KT WIND SPEED RADII AND 12-FT WAVE HEIGHT RADII ARE INCREASED
BASED ON SHIP REPORTS.
 
FORECASTER LAWRENCE
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL     22/1500Z 29.8N  57.5W    45 KTS
12HR VT     23/0000Z 30.5N  54.6W    45 KTS
24HR VT     23/1200Z 31.4N  51.2W    40 KTS
36HR VT     24/0000Z 31.9N  47.5W    40 KTS
48HR VT     24/1200Z 32.4N  45.0W    35 KTS
72HR VT     25/1200Z 32.0N  40.5W    30 KTS
 
 
NNNN