179 
 WTPA42 PHFO 140250
 TCDCP2
 
 HURRICANE FLOSSIE DISCUSSION NUMBER  22
 NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI   EP092007
 500 PM HST MON AUG 13 2007
 
 IT APPEARS THAT HURRICANE FLOSSIE IS BEGINNING TO FEEL THE EFFECTS 
 OF SLIGHTLY COOLER OCEAN TEMPERATURES AND INCREASING SOUTHERLY 
 SHEAR. WHILE OUTFLOW REMAINS GOOD TO THE NORTH...OUTFLOW APPEARS TO 
 BE HAMPERED TO THE SOUTH AND WE ARE BEGINNING TO SEE WEAKENING ALONG 
 THE SOUTHERN FLANK OF THE EYEWALL. CONVECTIVE CLOUD TOPS HAVE WARMED 
 OVER THE PAST SIX HOURS AND AIRCRAFT OBSERVATIONS SHOWED AN 
 EXTRAPOLATED SURFACE WIND OF 106 KT AT 0115Z AS WELL AS AN OPEN 
 EYEWALL ALONG THE SOUTHEAST FLANK. THIS IS IN LINE WITH CI VALUES OF 
 5.5...102 KT...FROM CPHC...JTWC AND SAB BETWEEN 2330Z AND 0000Z. WE 
 WILL INITIALIZE FLOSSIE AT 105 KT FOR THIS RUN...KEEPING THIS SYSTEM 
 AS A SAFFIR-SIMPSON CATEGORY 3 HURRICANE. 
 
 CONSENSUS TRACK GUIDANCE REMAINS PACKED THROUGH 24 HOURS...BUT 
 BEGINS TO DIVERGE SHARPLY AFTERWARDS...WITH CONB SIGNIFICANTLY RIGHT 
 OF THE OLD TRACK BEYOND 48 HOURS. BAMD REMAINS THE RIGHT OUTLIER. 
 THE NEW FORECAST TRACK...SITUATED ALONG THE NORTHERN EDGE OF THE 
 CONSENSUS ENVELOPE THROUGH 24 HOURS...LIES ALONG THE OLD TRACK 
 THROUGH 48 HOURS...THEN GRADUALLY DEVIATES TO THE RIGHT AT TAU 
 72...96 AND 120. THE RESULT IS AN ALMOST STRAIGHT LINE TRACK HEADING 
 TOWARDS THE WEST NORTHWEST. THIS TRACK MODIFICATION DOES NOT BECOME 
 SIGNIFICANT UNTIL FLOSSIE PASSES WEST OF 160W...BEYOND THE REALM OF 
 THE MAIN HAWAIIAN ISLANDS. THIS TRACK DOES INCREASE THE RISK FOR THE 
 NORTHWESTERN HAWAIIAN ISLANDS BEYOND KAUAI. WE FORECAST FLOSSIE WILL 
 GRADUALLY WEAKEN THROUGH 120 HOURS WITH THE ACCUMULATING EFFECTS OF 
 OCEAN COOLING AND INCREASING SHEAR...DROPPING BELOW HURRICANE 
 STRENGTH AT 120 HOURS. 
 
 SCATTEROMETER AND AIRCRAFT OBSERVATIONS SHOW THE 120 NM TROPICAL 
 STORM STRENGTH WIND RADIUS REMAINS VALID WITHIN THE NORTHWEST AND 
 NORTHEAST QUADRANTS. THIS RADIUS WILL REACH THE BIG ISLAND AS 
 FLOSSIE PASSES TO THE SOUTH...SO A TROPICAL STORM WARNING REMAINS IN 
 EFFECT FOR THE BIG ISLAND...AS WELL AS A HURRICANE WATCH. WITH THE 
 CURRENT FORECAST TRACK...THE ISLANDS FROM MAUI COUNTY TO KAUAI 
 COUNTY ARE NOT EXPECTED TO REQUIRE ANY TYPES OF WATCHES. 
 HOWEVER...ANY SIGNIFICANT DEVIATION OF THE TRACK TOWARD THE NORTH 
 MIGHT RESULT IN WATCHES OR WARNINGS FOR ADDITIONAL AREAS IN THE 
 HAWAIIAN ISLANDS.
  
 FORECAST POSITIONS AND MAX WINDS
  
 INITIAL      14/0300Z 15.9N 152.0W   105 KT
  12HR VT     14/1200Z 16.6N 153.8W   105 KT
  24HR VT     15/0000Z 17.6N 156.2W   100 KT
  36HR VT     15/1200Z 18.5N 158.5W    95 KT
  48HR VT     16/0000Z 19.4N 160.9W    90 KT
  72HR VT     17/0000Z 21.1N 165.2W    85 KT
  96HR VT     18/0000Z 22.5N 169.0W    70 KT
 120HR VT     19/0000Z 24.0N 172.9W    60 KT
  
 $$
 FORECASTER POWELL