WDPN31 PGTW 300900 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TYPHOON 12W (HINNAMNOR) WARNING NR 009// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 26.7N 135.4E INITIAL INTENSITY: 125 KTS GEOGRAPHIC REFERENCE: 408 NM EAST OF KADENA AB MOVEMENT PAST 6 HOURS: WESTWARD AT 18 KTS SIGNIFICANT WAVE HEIGHT: 43 FEET SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS TIGHTLY WRAPPING BANDS OF DEEP CONVECTION AROUND A HIGHLY SYMMETRIC 12NM EYE THAT IS NOW COMPLETELY CLOUD FREE. A 300412Z AMSR2 89GHZ MICROWAVE IMAGE DEPICTS A SYMMETRIC CORE WITH A BANDING FEATURE ALONG ITS EASTERN SIDE. THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON MSI AND AMSR2 IMAGERY. THE INITIAL INTENSITY OF 125 KTS IS ASSESSED WITH HIGH CONFIDENCE BASED ON A MAJORITY OF AGENCY DVORAK ESTIMATES SHOWING T6.5 AND BOTH CIMSS SATCON AND ADT SHOWING 122-127KTS. INITIAL WIND RADII BASIS: PERSISTENCE CURRENT STEERING MECHANISM: DEEP-LAYERED EXTENSION OF THE SUBTROPICAL RIDGE (STR) POSITIONED TO THE NORTH AGENCY DVORAK AND AUTOMATED FIXES: PGTW: T6.5 - 127 KTS RJTD: T6.5 - 127 KTS KNES: T6.0 - 115 KTS CIMSS SATCON: 122 KTS AT 300359Z CIMSS ADT: 127 KTS AT 300710Z FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE VWS: 15-20 KTS SST: 30-31 CELSIUS OUTFLOW: STRONG EQUATORWARD ANALYSIS CONFIDENCE: INITIAL POSITION: HIGH INITIAL INTENSITY: HIGH INITIAL WIND RADII: LOW 3. FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO THE FORECAST FROM THE PREVIOUS WARNING. FORECAST DISCUSSION: TY 12W IS FORECAST TO CONTINUE TRACKING GENERALLY WESTWARD THROUGH TAU 24 UNDER THE STEERING INFLUENCE OF THE STR TO THE NORTH. HAVING JUST COMPLETED AN EYE WALL REPLACEMENT CYCLE (ERC), 12W HAS REINTENSIFIED BACK TO 125 KTS AND REMAINS IN A FAVORABLE ENVIRONMENT MARKED BY WARM SEA SURFACE TEMPERATURES (30-31C), MODERATE VERTICAL WIND SHEAR (15-20KTS) AND STRONG OUTFLOW ALOFT. 12W IS FORECAST TO REACH A POTENTIAL PEAK INTENSITY OF 135KTS OR POSSIBLY HIGHER BY TAU 36. BY THIS TIME, TWO MAIN FACTORS BEGIN TO ALTER THE TRAJECTORY OF 12W. A MIDLATITUDE SHORTWAVE TROUGH IS EXPECTED TO DIG OVER THE KOREAN PENINSULA AND BREAK DOWN THE CURRENT STR TO THE NORTH. AS A RESULT THE STR TO THE WEST WILL TAKE PRIMARY CONTROL AND 12W IS FORECAST TO TRACK MORE EQUATORWARD ALONG ITS SOUTHWESTERN PERIPHERY UNTIL ENDING UP IN A COMPETING STEERING SYNOPTIC PATTERN, WITH A STR TO THE NORTHEAST AND WEST, AND A NEAR-EQUATORIAL RIDGE TO THE SOUTH. THE SECOND FACTOR BEING A POTENTIAL BINARY INTERACTION WITH 98W WHICH IS CONSOLIDATING 400NM TO THE SOUTH OF 12W, ALREADY WITHIN CAPTURE DISTANCE. AS THESE TWO FACTORS MANIFEST THE SYSTEM IS FORECAST TO BEGIN TO TRACK SOUTHWESTWARD AND NEAR TAU 48 AS THE STEERING ENVIRONMENT BECOMES INCREASINGLY COMPLICATED TRACK SPEEDS WILL SLOW AND UPWELLING WILL BEING TO SIGNIFICANTLY IMPACT INTENSITY. TAU 72 IS A SIGNIFICANT INFLECTION POINT AS MODELS AGREE 12W WILL EXECUTE A POLEWARD TURN AND TRACK NORTHWARD WITH A BULK OF THE GUIDANCE INDICATING A NORTH-NORTHWESTWARD AND EVENTUAL NORTHWARD TRACK THROUGH THE FORECAST PERIOD. AFTER THIS TURN NEAR TAU 72 THERE IS A POTENTIAL FOR REINTENSIFICATION THOUGH THE AMOUNT OF TIME SPENT QS OVER COOLER WATERS WILL HAVE A STRONG IMPACT ON LONG-RANGE INTENSITY FORECAST. MODEL DISCUSSION: NUMERICAL MODELS ARE IN TIGHT AGREEMENT THROUGH TAU 48, SHOWING A WESTWARD AND EVENTUAL SOUTHWESTWARD TURN. NEAR TAU 72 MODELS AGREE THAT 12W WILL EXECUTE A POLEWARD TURN THOUGH THE GUIDANCE VARIES ON THE EXACT TIMING AND FINAL HEADING. FOR THIS REASON THE INITIAL TRACK IS PLACED WITH HIGH CONFIDENCE WITH THE LONG RANGE TRACK FORECAST PLACED WITH MEDIUM CONFIDENCE. RELIABLE MODEL INTENSITY GUIDANCE IS PLACED WITH MEDIUM CONFIDENCE DUE TO A SIZABLE SPREAD IN INTENSITY SOLUTIONS. THE BULK OF THE GUIDANCE INDICATES AN INITIAL INTENSIFICATION PERIOD AFTER WHICH GRADUAL DECLINE THROUGH TAU 72 AFTER WHICH MODELS ARE SPLIT BETWEEN REINTENSIFICATION AND DISSIPATION THROUGH THE FORECAST PERIOD. FORECAST CONFIDENCE: TRACK 0 - 72 HR: HIGH TRACK 72-120 HR: MEDIUM INTENSITY 0 - 72 HR: MEDIUM INTENSITY 72-120 HR: LOW// NNNN