HURRICANE FLOSSIE DISCUSSION NUMBER 15
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI EP092007
1100 PM HST SAT AUG 11 2007
HURRICANE FLOSSIE CONTINUES TO HAVE AN EXTREMELY IMPRESSIVE SIGNATURE IN INFRARED SATELLITE IMAGERY THIS EVENING. FLOSSIE HAS A VERY WARM WELL DEFINED 20 NM DIAMETER EYE SURROUNDED BY A RING OF VERY COLD CLOUD TOPS. THE SYSTEM ALSO CONTINUES TO EXHIBIT A REMARKABLE OUTFLOW. HOWEVER...THE PREVIOUS INTENSIFICATION APPEARS TO HAVE BEEN REVERSED DURING THE PAST FEW HOURS. SATELLITE INTENSITY ESTIMATES SUGGESTED A SLIGHT WEAKENING...SO THE CURRENT ADVISORY SHOWED A DECREASE IN THE INITIAL MAXIMUM WIND SPEEDS TO 115 KT.
THE LONG TERM MOTION OF FLOSSIE SOUTH OF THE STRONG MID-PACIFIC OCEAN SUBTROPICAL RIDGE IS TOWARD 280 DEGREES AT 12 KT. THERE CONTINUE TO BE VERY SIGNIFICANT WOBBLES OF THE EYE THAT ARE CLEARLY EVIDENT IN SATELLITE IMAGERY. HOWEVER...IT APPEARS THAT THE THE MEAN TRACK OF FLOSSIE REMAINS VERY CLOSE TO THE PREVIOUS FORECASTS.
THE MOST RECENT OBJECTIVE GUIDANCE PACKAGE RECEIVED AT CPHC HAS SHOWN SOME DECREASE IN THE SPREAD OF THE FORECAST TRACKS AS FLOSSIE APPROACHES THE HAWAIIAN ISLANDS. THE LATEST RUNS OF THE NOGAPS AND GFDL MODELS HAVE SHIFTED MUCH FARTHER TO THE LEFT NOW. AS A RESULT...THE CONSENSUS MODELS HAVE ALSO BEEN NUDGED MORE TO THE LEFT. THIS PROVIDES A LITTLE MORE CONFIDENCE IN THE TRACK FORECAST. THIS FORECAST DOES NOT SHOW ANY SIGNIFICANT DEVIATION FROM THE PREVIOUS TRACK.
THE INTENSITY FORECAST REMAINS THE BIGGEST QUESTION AT THE MOMENT. THE GLOBAL MODELS CONTINUE TO SHOW INCREASING VERTICAL WIND SHEAR IN 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 IS MORE IN LINE WITH THE GFDL GUIDANCE. THERE IS A LITTLE BETTER CONFIDENCE IN THIS MODEL OUTPUT FROM THE GFDL...SINCE THE TRACK HAS MOVED MORE IN LINE WITH THE OTHER TRACK GUIDANCE. KEEP IN MIND THAT OUR ERRORS IN FORECASTING INTENSITY ARE STILL LARGE...ESPECIALLY AT 48 AND 72 HOURS...AND BEYOND.
ALL THOSE WHO ARE FOLLOWING FLOSSIE ARE URGED NOT FOCUS ON THE ACTUAL FORECAST TRACK OF THE CALM EYE. THE STRONG WINDS IN THE EYE WALL SURROUNDING THE CENTER OF THE HURRICANE EXTEND FAR BEYOND THIS LINE. THEREFORE...EVEN THOUGH THE EYE OF FLOSSIE MAY PASS JUST SOUTH OF THE HAWAIIAN ISLANDS...IT COULD STILL BRING STRONG WINDS AND HEAVY RAINS TO PORTIONS OF THE ISLANDS EARLY NEXT WEEK BASED ON THE CURRENT FORECAST. PLEASE CONTINUE TO MONITOR FUTURE ADVISORIES FOR THE LATEST INFORMATION ON THIS VERY STRONG HURRICANE.
FORECAST POSITIONS AND MAX WINDS
INITIAL 12/0900Z 13.6N 143.5W 115 KT
12HR VT 12/1800Z 14.0N 145.2W 110 KT
24HR VT 13/0600Z 14.7N 147.4W 95 KT
36HR VT 13/1800Z 15.4N 149.4W 95 KT
48HR VT 14/0600Z 16.2N 151.4W 90 KT
72HR VT 15/0600Z 17.6N 155.4W 70 KT
96HR VT 16/0600Z 18.9N 159.0W 50 KT
120HR VT 17/0600Z 20.3N 162.3W 45 KT
$$
FORECASTER HOUSTON