996 
 WTPA42 PHFO 121517
 TCDCP2
 
 HURRICANE FLOSSIE DISCUSSION NUMBER  16
 NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI   EP092007
 500 AM HST SUN AUG 12 2007
 
 DANGEROUS HURRICANE FLOSSIE CONTINUES TO TRAVEL ACROSS THE OPEN 
 WATERS OF THE NORTH CENTRAL PACIFIC OCEAN. THE SYSTEM HAS TAKEN 
 ADVANTAGE OF ITS VERY FAVORABLE TROPICAL ENVIRONMENT FAR FROM ANY 
 SIGNIFICANT LAND MASSES. THE CURRENT MOTION IS 280 DEGREES AT 10 KT. 
 AS WAS NOTED 6 HOURS EARLIER...SHORT-TERM WOBBLES OF THE EYE ARE 
 CLEARLY EVIDENT IN SATELLITE IMAGERY. HOWEVER...IT APPEARS THE 
 AVERAGE TRACK OF FLOSSIE REMAINS CLOSE TO THE PREVIOUS FORECASTS. 
  
 IN ADDITION TO THE WELL-DEFINED EYE AND EYEWALL STRUCTURE OF 
 HURRICANE FLOSSIE...THE TROPICAL CYCLONE HAS MAINTAINED AN EXTREMELY 
 IMPRESSIVE OUTFLOW OVERNIGHT. DURING A RECENT COORDINATION CALL WITH 
 THE TYPHOON DUTY OFFICER AT JTWC...IT WAS POINTED OUT THAT AN UPPER 
 TROPOSPHERIC TROUGH HAS BEEN DIGGING SOUTHWARD ALONG LONGITUDE 137W. 
 THIS TROUGH AXIS...WHICH IS NORTH NORTHEAST OF FLOSSIE APPEARS TO BE 
 PROVIDING AN EXCELLENT OUTFLOW CHANNEL. THE POSITIVE INFLUENCE OF 
 THIS UPPER LEVEL ANTICYCLONIC CIRCULATION ALONG WITH THE WARM 
 TROPICAL OCEAN APPEAR TO BE MAINTAINING FLOSSIE/S INTENSITY. THE 
 UW/CIMMS ADT ESTIMATE FOR 1130 UTC WAS 6.0. THE MOST RECENT 
 SATELLITE INTENSITY ESTIMATES OF 6.0 FROM JTWC AND 6.5 FROM SAB AND 
 HFO SUGGESTED THAT FLOSSIE HAS MAXIMUM WIND SPEEDS OF 120 KT. 
 
 THE LATEST MODEL TRACK GUIDANCE CONTINUES TO BE MORE TIGHTLY 
 CLUSTERED IN THE 72 TO 120 HOUR FORECAST TIME FRAME THAN THE RUNS 
 MADE 12 HOURS AGO. NOGAPS CONTINUES TO BE THE MAJOR MODEL BRINGING 
 FLOSSIE ACROSS THE HAWAIIAN ISLANDS...WITH THE GFDL RUN BRINGING THE 
 SYSTEM CLOSE TO SOUTH POINT ON THE BIG ISLAND AFTER 72 HOURS. 
 THEREFORE...THE CONSENSUS MODELS WERE FOLLOWED CLOSELY IN THE LATEST 
 FORECAST TRACK. 
 
 ONCE AGAIN...THE INTENSITY FORECAST REMAINS THE BIGGEST QUESTION AT 
 THE MOMENT. THE GLOBAL MODELS CONTINUE TO SHOW INCREASING VERTICAL 
 WIND SHEAR ALONG THE FUTURE PATH OF FLOSSIE. THIS SHEAR APPEARS TO 
 BE THE MOST HOSTILE BEYOND THE 48 HOUR TIME FRAME. SLIGHTLY COOLER 
 SEA SURFACE TEMPERATURES AND DECREASED OCEAN HEAT CONTENT ALONG THE 
 FORECAST TRACK ALSO IMPLY FUTURE WEAKENING OF THE TROPICAL CYCLONE. 
 THE CURRENT INTENSITY FORECAST REMAINS IN LINE WITH THE GFDL 
 GUIDANCE. KEEP IN MIND THAT OUR ERRORS IN FORECASTING INTENSITY ARE 
 STILL LARGE...ESPECIALLY AT 4