WDPN32 PGTW 301500 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TYPHOON 06W (KHANUN) WARNING NR 014// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 20.4N 132.4E INITIAL INTENSITY: 90 KTS GEOGRAPHIC REFERENCE: 445 NM SOUTHEAST OF KADENA AB MOVEMENT PAST 6 HOURS: NORTH-NORTHWESTWARD AT 08 KTS SIGNIFICANT WAVE HEIGHT: 31 FEET SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: TYPHOON (TY) 06W HAS RAPIDLY INTENSIFIED 40 KNOTS OVER THE PAST 24 HOURS FROM 50 KNOTS AT 291200Z TO THE INITIAL INTENSITY OF 90 KNOTS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY DEPICTS A ROUND 15NM EYE, WHICH SUPPORTS THE INITIAL POSITION WITH HIGH CONFIDENCE. A 301103Z GMI 89GHZ MICROWAVE IMAGE DEPICTS AN OBLONG EYEWALL WITH A BREAK OVER THE NNW QUADRANT AND TIGHTLY-CURVED SPIRAL BANDING. THE GMI 37GHZ MICROWAVE IMAGE SHOWS A MORE SYMMETRIC MICROWAVE EYE FEATURE AND ALSO SUPPORTS THE INITIAL POSITION. ANIMATED WATER VAPOR IMAGERY CONTINUES TO SHOW STRONG EQUATORWARD OUTFLOW AND ROBUST POLEWARD OUTFLOW, WHICH HAS ALLOWED CORE CONVECTION TO CONSOLIDATE RAPIDLY OVER THE PAST 12 HOURS. THE INITIAL INTENSITY IS ASSESSED AT 90 KNOTS WITH MEDIUM CONFIDENCE AND IS BASED ON THE PGTW, RCTP DVORAK ESTIMATES, THE CIMSS ADT ESTIMATE AS WELL AS A PARTIAL 300905Z RCM-3 SAR IMAGE SHOWING 87 KNOT WINDS OVER THE EASTERN QUADRANT. THE KNES DVORAK ESTIMATE OF T5.5 (102 KNOTS) IS WITHIN THE RANGE OF UNCERTAINTY WITH THE 301330Z ADT ESTIMATES UP TO 5.3 (97 KNOTS) AND THE RAW ADT ESTIMATES STEADY AT ABOUT T6.0 (115 KNOTS); THESE ESTIMATES SUGGEST THE INTENSITY COULD JUMP HIGHER WITHIN THE NEXT SIX TO TWELVE HOURS. INITIAL WIND RADII BASIS: PERSISTENCE CURRENT STEERING MECHANISM: DEEP-LAYERED SUBTROPICAL RIDGE (STR) CENTERED SE OF TOKYO WITH RIDGE EXTENDING SOUTHWARD. AGENCY DVORAK AND AUTOMATED FIXES: PGTW: T5.0 - 90 KTS RJTD: T4.0 - 65 KTS RCTP: T5.0 - 90 KTS KNES: T5.5 - 102 KTS CIMSS SATCON: 87 KTS AT 301035Z CIMSS ADT: 92 KTS AT 301200Z D-PRINT: 96 KTS AT 301400Z FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: HIGHLY FAVORABLE VWS: 0-5 KTS SST: 29-30 CELSIUS OUTFLOW: STRONG RADIAL ANALYSIS CONFIDENCE: INITIAL POSITION: HIGH INITIAL INTENSITY: MEDIUM INITIAL WIND RADII: MEDIUM 3. FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: PEAK INTENSITY HAS BEEN INCREASED TO 115 KNOTS. FORECAST TRACK SPEEDS HAVE BEEN SLOWED SIGNIFICANTLY AFTER TAU 72. FORECAST DISCUSSION: THE JTWC TRACK FORECAST REMAINS HIGHLY CONSISTENT WITH THE PREVIOUS JTWC TRACK FORECAST WITH NO SIGNIFICANT CHANGE TO THE CPA AND CPA DISTANCE TO KADENA AB. OVERALL, OVER THE PAST 3.5 DAYS, JTWC FORECASTS HAVE REMAINED WITHIN A 50NM ENVELOPE JUST TO THE SOUTH OF OKINAWA. TY 06W WILL TURN GRADUALLY WEST- NORTHWESTWARD AFTER TAU 24 AND CONTINUE TRACKING WEST-NORTHWESTWARD THROUGH TAU 72 UNDER THE STEERING INFLUENCE OF THE STR POSITIONED TO THE NORTH AND NORTHEAST. BASED ON THE HIGHLY FAVORABLE ENVIRONMENTAL CONDITIONS AND AFOREMENTIONED RAW ADT ESTIMATES, THE PEAK INTENSITY HAS BEEN INCREASED TO 115 KNOTS AT TAU 36. AFTER TAU 72, THE SYSTEM IS NOW FORECAST TO SLOW SIGNIFICANTLY AS IT APPROACHES THE EASTERN COAST OF CHINA WITH LANDFALL EXPECTED NEAR TAU 96. DUE TO THE LARGE SIZE OF THE SYSTEM AND ITS EXPANSIVE GALE-FORCE WINDS, NEAR GALE- FORCE WINDS MAY PERSIST AFTER THE SYSTEM TRACKS WEST OF OKINAWA. MODEL DISCUSSION: THE 300600Z ECMWF (EPS) AND GFS (GEFS) ENSEMBLES INDICATE A BIFURCATION IN PROBABILISTIC GUIDANCE WITH TWO DISTINCT CLUSTERS. THE FIRST CLUSTER SUPPORTS A WNW TRACK INTO EAST CENTRAL CHINA AND DISSIPATION SCENARIO. THE SECOND CLUSTER REVEALS A SLOW POLEWARD TRACK OVER THE EAST CHINA SEA TOWARD THE KOREAN PENINSULA (NOTE: THIS COVERS THE NEXT 5 DAYS ONLY). DETERMINISTIC GUIDANCE REMAINS IN TIGHT AGREEMENT THROUGH TAU 48 WITH A CROSS-TRACK SPREAD NEAR OKINAWA RANGING FROM 50NM AT TAU 36 TO 80 NM AT TAU 48. RAPID INTENSIFICATION (RI) WILL LIKELY CONTINUE FOR THE NEXT 24 TO 36 HOURS WITH RI GUIDANCE TRIGGERED AND THE 300600Z COAMPS-TC ENSEMBLE INDICATING A 20 TO 30 PERCENT PROBABILITY OF RI. AFTER TAU 48, DETERMINISTIC GUIDANCE DIVERGES WITH A VERY NOTICEABLE DECREASE IN TRACK SPEEDS OVER EASTERN CHINA OR OFF THE COAST. CONSEQUENTLY, CONFIDENCE IS LOW IN THE EXTENDED PERIOD. THE GFS DETERMINISTIC SOLUTION IS PARTICULARLY PROBLEMATIC WITH GFS QUICKLY BREAKING DOWN THE STR AND SHOWING A STALL NEAR 125E; THIS SCENARIO WILL BE WATCHED CAREFULLY SINCE IT COULD IMPACT OKINAWA. THE JTWC FORECAST PHILOSOPHY CONTINUES TO FAVOR THE WNW MODEL GROUPING AND THE ECMWF ENSEMBLE (EPS) SINCE GFS CONTINUES TO TRACK THE SYSTEM DIRECTLY INTO THE STR TO THE NORTH WITH NO DYNAMIC SHORTWAVE TROUGH EVIDENT IN THE ZONAL MIDLATITUDE FLOW. FORECAST CONFIDENCE: TRACK 0 - 72 HR: MEDIUM TRACK 72-120 HR: LOW INTENSITY 0 - 72 HR: MEDIUM INTENSITY 72-120 HR: LOW// NNNN