000 WTPZ44 KNHC 092032 TCDEP4 TROPICAL STORM FLOSSIE DISCUSSION NUMBER 5 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP092007 200 PM PDT THU AUG 09 2007 THE ORGANIZATION OF FLOSSIE CONTINUES TO IMPROVE...WITH A FORMATIVE EYE APPARENT IN MICROWAVE AND CONVENTIONAL SATELLITE IMAGERY. DVORAK INTENSITY ESTIMATES FROM TAFB AND SAB WERE 55 KT...AND A QUIKSCAT PASS FROM 14Z THIS MORNING SUGGESTED THAT WINDS WERE CLOSE TO OR JUST BELOW THE CONCURRENT SATELLITE ESTIMATES. CONSEQUENTLY... THE ADVISORY INTENSITY IS INCREASED TO 55 KT. THE INITIAL MOTION IS 265/13...ABOUT THE SAME AS BEFORE. FLOSSIE WILL BE MOVING TO THE SOUTH OF A WEAKNESS IN THE SUBTROPICAL RIDGE OVER THE NEXT DAY OR TWO...WHICH COULD SLOW THE FORWARD MOTION A BIT...BUT THE SMALL CIRCULATION OF FLOSSIE IS UNLIKELY TO INTERACT SIGNIFICANTLY WITH THIS WEAKNESS. AFTER THAT...A NARROW MID-LEVEL RIDGE IS EXPECTED TO KEEP THE CYCLONE ON A WEST OR WEST-NORTHWEST TRACK THROUGH THE FORECAST PERIOD. MODEL GUIDANCE IS LARGELY UNCHANGED FROM THIS MORNING...EXCEPT FOR THE UKMET WHICH HAS SHIFTED NORTH AND IS NOW CLOSE TO THE HWRF...GFDL...AND GFS. THE OFFICIAL FORECAST FOLLOWS A BLEND OF THESE MODELS. AN ALTERNATIVE TRACK...FASTER AND FARTHER SOUTH...IS OFFERED BY THE NOGAPS...ECMWF...AND FSSE. IN THE SHORT TERM...SOME ADDITIONAL INTENSIFICATION SEEMS LIKELY. THE OUTFLOW PATTERN IS RESTRICTED TO THE EAST BUT LOOKS GOOD ELSEWHERE. SSTS ALONG THE PROJECTED TRACK WILL REMAIN ABOVE 27C FOR ANOTHER 36 HOURS OR SO. THE LOW-LEVEL INFLOW PATTERN DOES NOT SEEM IDEAL...HOWEVER...WITH A STABLE AIR MASS TO THE NORTHWEST OF THE CYCLONE AND THE MOIST SOUTHERLY FLOW IN THE SOUTHEAST QUADRANT SEEMINGLY RUNNING AWAY FROM THE CENTER. MOST...BUT NOT ALL THE OBJECTIVE GUIDANCE MAKES FLOSSIE A HURRICANE. AFTER 48 HOURS...COOLER SSTS SHOULD INDUCE A WEAKENING TREND. HOW FAST FLOSSIE DECLINES NEAR THE END OF THE FORECAST PERIOD WILL BE GOVERNED BY THE UPPER FLOW...WHICH IS FORECAST TO EVOLVE VERY DIFFERENTLY BY THE VARIOUS LARGE-SCALE MODELS. THE GFS MAINTAINS A RELATIVELY FAVORABLE UPPER ENVIRONMENT...WHILE THE ECMWF AND UKMET HAVE MUCH HIGHER SHEAR. IT'S DIFFICULT TO TELL WHICH SCENARIO WILL VERIFY...BUT THE OFFICIAL FORECAST AT THIS POINT CONSERVATIVELY ASSUMES THAT THE UPPER FLOW WILL NOT BECOME VERY HOSTILE. FORECAST POSITIONS AND MAX WINDS INITIAL 09/2100Z 12.8N 132.4W 55 KT 12HR VT 10/0600Z 12.8N 134.3W 60 KT 24HR VT 10/1800Z 13.0N 136.3W 65 KT 36HR VT 11/0600Z 13.3N 138.4W 65 KT 48HR VT 11/1800Z 13.6N 140.4W 65 KT 72HR VT 12/1800Z 14.5N 144.5W 55 KT 96HR VT 13/1800Z 15.5N 149.0W 50 KT 120HR VT 14/1800Z 16.5N 153.0W 45 KT $$ FORECASTER FRANKLIN