000 WTNT42 KNHC 170250 TCDAT2 TROPICAL DEPRESSION ANA DISCUSSION NUMBER 20 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022009 1100 PM AST SUN AUG 16 2009 RADAR IMAGERY FROM GUADELOUPE SUGGESTS THAT THE LOW-LEVEL CENTER OF ANA HAS TURNED TOWARD THE WEST-NORTHWEST AND IS MOVING QUICKLY AT AN INITIAL MOTION OF 285/23. ALTHOUGH SOME DEEP CONVECTION HAS RECENTLY RE-DEVELOPED...IT IS ORIENTED LINEARLY ALONG A NORTH-SOUTH AXIS AND APPEARS MORE REPRESENTATIVE OF A TROPICAL WAVE. THE CENTER APPEARS REASONABLY WELL-DEFINED ON THE GUADELOUPE RADAR BUT THIS IS LIKELY DEPICTING A MID-LEVEL CIRCULATION RATHER THAN ONE AT THE SURFACE. AT THIS TIME WE WOULD RATHER NOT STOP ADVISORIES WHILE THE SYSTEM IS MOVING ACROSS THE LESSER ANTILLES. HOWEVER IF SURFACE OBSERVATIONS FROM THOSE ISLANDS CONFIRM THE LACK OF A CENTER...ADVISORIES WILL BE TERMINATED EARLY MONDAY. VERY FEW OF THE DYNAMICAL MODELS SHOW ANY RE-STRENGTHENING...AND A FEW SUCH AS THE GFS...HWRF...AND GFDL LOSE THE VORTEX AFTER ABOUT 36 HOURS. THE TRACK GUIDANCE INDICATES THAT ANA SHOULD BE MOVING OVER THE HIGH TERRAIN OF HISPANIOLA IN 24-36 HOURS...AND IT IS DOUBTFUL THAT ITS CIRCULATION WILL MAKE IT ACROSS THAT ISLAND INTACT. THE OFFICIAL FORECAST SHOWS ANA BECOMING A REMNANT LOW BY 36 HOURS AFTER IT BEGINS CROSSING LAND...BUT IT IS POSSIBLE THAT IT COULD BECOME AN OPEN WAVE AT ANY TIME. THE TRACK FORECAST IS SHIFTED NORTH OF THE PREVIOUS FORECAST TOWARD THE SHALLOW LAYER BAM TRACK AND IN LINE WITH THE GFS AND ECMWF SINCE IT IS ASSUMED THAT THE REMNANT CIRCULATION WILL BE STEERED BY THE LOW-LEVEL FLOW. TROPICAL STORM WATCHES WILL REMAIN IN EFFECT UNTIL IT IS CLEAR THAT ANA WILL NOT RE-STRENGTHEN OR UNTIL IT PASSES THE LEEWARD ISLANDS LATER TONIGHT. FORECAST POSITIONS AND MAX WINDS INITIAL 17/0300Z 16.0N 61.2W 30 KT 12HR VT 17/1200Z 16.7N 64.4W 30 KT 24HR VT 18/0000Z 18.1N 68.6W 30 KT 36HR VT 18/1200Z 19.6N 72.6W 25 KT...REMNANT LOW 48HR VT 19/0000Z 21.2N 76.0W 25 KT...REMNANT LOW 72HR VT 20/0000Z 24.0N 81.0W 25 KT...REMNANT LOW 96HR VT 21/0000Z 26.0N 84.0W 25 KT...REMNANT LOW 120HR VT 22/0000Z 28.0N 86.0W 25 KT...REMNANT LOW $$ FORECASTER BERG