WTPA42 PHFO 270240 TCDCP2 HURRICANE IOKE DISCUSSION NUMBER 29 NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI CP012006 500 PM HST SAT AUG 26 2006 HURRICANE IOKE IS ABOUT TO CROSS THE DATELINE AND BECOME TYPHOON IOKE...STILL AT CATEGORY 5 STATUS. SUBJECTIVE DVORAK ESTIMATES FOR 26/2330Z OF 7.0 FROM CPHC AND KGWC...AND 6.5 FROM SAB AND JTWC...PROMPT US TO KEEP INITIAL INTENSITY AT 140 KT. AODT FROM CPHC IS 6.9. IOKE MAINTAINS A WELL-FORMED EYE WITH A CENTRAL TEMP OF +3.8C AND A SURROUNDING CLOUD REGION TEMP OF -72.0C. IOKE APPEARS TO HAVE COMPLETED AN EYEWALL REPLACEMENT CYCLE WITH LITTLE OR NO DECREASE IN INTENSITY OVER THE PAST 12 HOURS. MODEL TRACK GUIDANCE IS NICELY CLUSTERED...WITH GUNS..GUNA AND CONU IN CLOSE AGREEMENT WITH...STRANGELY ENOUGH...BAMS. NOGAPS AND BAMD REPRESENT THE RIGHT AND LEFT OUTLIERS...RESPECTIVELY. TRACK CLUSTER GUIDANCE CONTINUES THE TAKE IOKE ALONG A WEST TO WEST SOUTHWESTERLY COURSE THROUGH 36 HOURS AS THIS SYSTEM RESPONDS TO WEAK RIDGING TO ITS NORTHWEST. THE 18Z GFS75 SHOWS THIS RIDGE WILL SPLIT ALONG IOKE/S PATH BEYOND 36 HOURS...DRAWING IOKE DUE WESTWARD BY 48 HOURS THEN NORTHWESTWARD THROUGH 72...96 AND 120 HOURS. THE FORECAST TRACK IS VERY CLOSE TO THE PREVIOUS TRACK THROUGH 72 HOURS...THEN DEVIATES SLIGHTLY TO THE LEFT OF THE PREVIOUS TRACK AT 96 AND 120 HOURS. SATELLITE LOOPS SHOW IOKE HAS BEGUN TO TAKE A MORE WEST SOUTHWESTERLY TRACK VERSUS THE SOUTHWESTERLY TRACK NOTED EARLIER TODAY. INITIAL FORWARD MOTION HAS INCREASED AS WELL AND IS INCREASED SLIGHTLY THROUGHOUT THE ENTIRE FORECAST TRACK. WHILE THE FORECAST TRACK TAKES IOKE NORTHEAST OF WAKE ISLAND AT POINT OF CLOSEST APPROACH BETWEEN 84 AND 96 HOURS...IT IS IMPORTANT TO NOTE THAT THE 18Z GFS75 TAKES THIS SYSTEM ALMOST DIRECTLY OVER THAT ISLAND AT 96 HOURS. IOKE WILL LIKELY GO THROUGH SEVERAL EYEWALL REPLACEMENT CYCLES OVER THE COMING DAYS...RESULTING IN SHORT TERM STRENGTH FLUCTUATIONS. HOWEVER...MODEL GUIDANCE KEEPS IOKE AT OR NEAR ITS CURRENT STRENGTH THROUGH 120 HOURS. NOGAPS AND UKMET ARE RATHER STEADY BUT...AS AN OUTLIER...GFDL WANTS TO STRENGTHEN IOKE TO 170 KT AT 96 HOURS. INCREASING SST AND LOW SHEAR ALONG THE FORECAST TRACK WILL...AT THE VERY LEAST...GREATLY SLOW IOKE/S DECAY AT HIGHER LATITUDES. THEREFORE...THE INTENSITY FORECAST IS UNCHANGED FROM THE PREVIOUS PACKAGE. IOKE COULD ENTER THE RECORD BOOKS FOR LONGEVITY AS A CATEGORY 4 OR GREATER STORM. THIS IS THE FINAL DISCUSSION FROM THE CENTRAL PACIFIC HURRICANE CENTER ON THIS SYSTEM. REFER TO THE BULLETIN BY RSMC TOKYO HEREAFTER. FORECAST POSITIONS AND MAX WINDS INITIAL 27/0300Z 17.7N 179.3W 140 KT 12HR VT 27/1200Z 17.2N 179.1E 140 KT 24HR VT 28/0000Z 17.0N 177.0E 140 KT 36HR VT 28/1200Z 17.0N 175.1E 140 KT 48HR VT 29/0000Z 17.3N 173.2E 140 KT 72HR VT 30/0000Z 18.5N 169.7E 140 KT 96HR VT 31/0000Z 20.8N 166.4E 140 KT 120HR VT 01/0000Z 23.6N 163.1E 135 KT $$ FORECASTER POWELL