000 WTNT42 KNHC 171500 TCDAT2 TROPICAL DEPRESSION ANA DISCUSSION NUMBER 22 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022009 1100 AM AST MON AUG 17 2009 THE CENTER OR WAVE AXIS OF ANA PASSED OVER BUOY 42060 AROUND 0830Z...AND IF A CENTER EXISTED AT THAT TIME IT WAS SOUTH OF THE BUOY. THERE WAS ONE SHIP REPORT WITH A LIGHT WEST WIND AT 12Z. SINCE THAT TIME...NEW CONVECTION WITH A MID-LEVEL SPIN HAS DEVELOPED NEAR THE SOUTHEAST COAST OF PUERTO RICO. GIVEN THESE HINTS...WE WILL CONTINUE ADVISORIES AT LEAST UNTIL A RECONNAISSANCE AIRCRAFT INVESTIGATES ANA THIS AFTERNOON. WITH A CENTER POSITION ESTIMATE BASED ON A BLEND OF CONTINUITY AND THE MID-LEVEL ROTATION SEEN IN THE RADAR DATA...THE INITIAL MOTION IS 285/24. ANA IS EXPECTED TO CONTINUE ON A GENERAL WEST- NORTHWESTWARD TRACK TO THE SOUTH OF THE SUBTROPICAL RIDGE FOR THE NEXT COUPLE OF DAYS...ALTHOUGH SOME ERRATIC MOTION IS POSSIBLE IN THE SHORT TERM GIVEN THE POOR DEFINITION OF THE CIRCULATION... INTERACTION WITH LAND...AND POTENTIAL REFORMATION OF THE CENTER. THE OFFICIAL FORECAST FOLLOWS A BLEND OF THE GFS AND ECMWF SOLUTIONS FOR THE 850 MB VORTICITY CENTER. TOWARD THE END OF THE FORECAST PERIOD...ANA OR ITS REMNANTS COULD BE EMBEDDED WITHIN WEAK STEERING OVER OR NEAR THE GULF OF MEXICO...AND THE OFFICIAL FORECAST CALLS FOR A GRADUAL SLOWING OF THE FORWARD SPEED. THE INTENSITY FORECAST IS COMPLICATED BY THE UNCERTAIN EXISTENCE OF AN ACTUAL TROPICAL CYCLONE...THE LAND MASSES IN THE PATH OF THE SYSTEM...AND HIGHLY DIVERGENT OBJECTIVE GUIDANCE. THE ENVIRONMENT OF ANA IS STILL CHARACTERIZED BY SOUTHWESTERLY SHEAR. THE DYNAMICAL MODELS...BOTH GLOBAL AND REGIONAL...ALMOST UNANIMOUSLY DISSIPATE THE CYCLONE...WHILE THE STATISTICAL MODELS SHOW RESTRENGHENING. IF ANA SURVIVES ITS PATH OVER THE GREATER ANTILLES AND EMERGES TO THE NORTH OF THE DOMINICAN REPUBLIC...THE GLOBAL MODELS SUGGEST THAT A MORE FAVORABLE UPPER WIND PATTERN WILL BE PRESENT THERE. CONSEQUENTLY...THE OFFICIAL FORECAST MAINTAINS ANA AS A TROPICAL CYCLONE THROUGH THE FORECAST PERIOD. THIS IS...ADMITTEDLY... SOMETHING OF A HEDGE BETWEEN TWO MORE LIKELY ALTERNATIVES...THAT OF A TROPICAL STORM NORTH OF THE ISLANDS OR IMMINENT DISSIPATION. FORECAST POSITIONS AND MAX WINDS INITIAL 17/1500Z 17.3N 66.2W 30 KT 12HR VT 18/0000Z 18.6N 69.4W 30 KT...INLAND 24HR VT 18/1200Z 20.5N 73.7W 30 KT 36HR VT 19/0000Z 22.3N 77.0W 30 KT 48HR VT 19/1200Z 23.7N 79.4W 30 KT 72HR VT 20/1200Z 26.5N 82.5W 30 KT 96HR VT 21/1200Z 28.0N 83.0W 30 KT 120HR VT 22/1200Z 30.0N 83.0W 25 KT...INLAND $$ FORECASTER FRANKLIN/CANGIALOSI