Hurricane FLOSSIE

ZCZC MIATCDEP4 ALL
TTAA00 KNHC DDHHMM
HURRICANE FLOSSIE DISCUSSION NUMBER  12
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   EP092007
800 AM PDT SAT AUG 11 2007
 
FLOSSIE HAS CONTINUED TO INTENSIFY THIS MORNING...WITH A MORE
SYMMETRIC AND SOLID RING OF EYEWALL CLOUD TOPS NEAR -75C AROUND
12Z.  ACCORDINGLY...SUBJECTIVE AND OBJECTIVE DVORAK INTENSITY
ESTIMATES AT THAT TIME WERE A CONSENSUS T6.0 OR 115 KT...AND THAT
IS THE ADVISORY INTENSITY. AN OVERPASS BY AMSR-E AT 1050Z REVEALS A
SINGLE EYEWALL AND NO APPARENT SIGNS OF ANY IMPENDING INNER CORE
STRUCTURAL CHANGES. SINCE 12Z THE INFRARED CLOUD TOP TEMPERATURES
HAVE RISEN SLIGHTLY...SO IT IS POSSIBLE THAT THE HURRICANE HAS
REACHED AN INTENSITY PLATEAU. THE UNDERLYING SEA-SURFACE
TEMPERATURES ALONG THE FORECAST TRACK WILL BE COOLER FROM THIS
POINT FORWARD...WHILE GLOBAL MODELS INDICATE THAT WIND SHEAR WILL
BEGIN INCREASING IN ABOUT 72 HOURS. THEREFORE THE OFFICIAL FORECAST
CALLS FOR FLOSSIE TO START GRADUALLY WEAKENING LATER TODAY...WITH
THE PACE OF DECLINE PICKING UP WHEN THE SHEAR INCREASES ON DAY 3.
THIS FORECAST IS CLOSE TO A CONSENSUS OF THE VARIOUS INTENSITY
GUIDANCE MODELS. EXCEPT FOR THE FSSE...ALL OF THE INTENSITY
GUIDANCE FORECASTS FLOSSIE TO DROP BELOW HURRICANE STATUS BEYOND 72
HOURS.

THE HURRICANE CONTINUES DUE WESTWARD...AND THE INITIAL MOTION IS A
SLIGHTLY WOBBLY 270 DEGREES AT 10 KNOTS.  WE CAN SAY FOR SURE NOW
THAT THE CENTER OF THE CYCLONE HAS CROSSED 140 DEGREES WEST INTO
THE CENTRAL PACIFIC BASIN.  ONCE AGAIN THE OFFICIAL TRACK FORECAST
HAS NOT CHANGED APPRECIABLY AND REMAINS ROUGHLY IN THE MIDDLE OF
THE GUIDANCE ENVELOPE.  THE GUIDANCE SPREAD REMAINS LARGE...
HOWEVER...ESPECIALLY LATE IN THE FORECAST PERIOD.  THE EVENTUAL
TRACK HINGES LARGELY ON JUST HOW STRONG THE SUBTROPICAL RIDGE IS TO
THE NORTH OF FLOSSIE IN A FEW DAYS.  MOST OF THE MODELS FORECAST
THE RIDGE CURRENTLY CENTERED OVER HAWAII TO WEAKEN SOMEWHAT...WHICH
SHOULD RESULT IN A TRACK THAT BENDS EVER SO GRADUALLY TO THE RIGHT. 
THE MAJORITY OF THE MODELS HOLD ONTO ENOUGH RIDGING TO KEEP THE
CENTER OF A WEAKENING FLOSSIE SOUTH OF THE HAWAIIAN ISLANDS...
ALTHOUGH A TRACK FARTHER NORTH THAN INDICATED BY THE OFFICIAL
FORECAST CANNOT BE RULED OUT.
 
THIS IS THE LAST ADVISORY ON FLOSSIE FROM THE NATIONAL HURRICANE
CENTER.  FUTURE ADVISORIES WILL BE ISSUED BY THE CENTRAL PACIFIC
HURRICANE CENTER IN HONOLULU HAWAII.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      11/1500Z 12.7N 140.2W   115 KT
 12HR VT     12/0000Z 12.9N 141.8W   115 KT
 24HR VT     12/1200Z 13.3N 143.9W   105 KT
 36HR VT     13/0000Z 13.7N 146.0W    95 KT
 48HR VT     13/1200Z 14.1N 148.1W    85 KT
 72HR VT     14/1200Z 15.5N 152.5W    70 KT
 96HR VT     15/1200Z 17.0N 156.5W    55 KT
120HR VT     16/1200Z 18.5N 160.0W    45 KT
 
$$
FORECASTER KNABB
 
NNNN