WDPN33 PGTW 181500 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TYPHOON 16W (NANMADOL) WARNING NR 024// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 31.9N 130.6E INITIAL INTENSITY: 80 KTS GEOGRAPHIC REFERENCE: 85 NM SOUTH-SOUTHEAST OF SASEBO, JAPAN MOVEMENT PAST 6 HOURS: NORTHWARD AT 12 KTS SIGNIFICANT WAVE HEIGHT: 35 FEET SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS A LARGE COLD DENSE OVERCAST (CDO) WITH BANDS OF CONVECTION WRAPPING INTO A FULLY OBSCURED LOW LEVEL CIRCULATION CENTER (LLCC). AN 180948Z SSMIS 89GHZ MICROWAVE IMAGE COUPLED WITH ANIMATED RADAR IMAGERY REVEALS AN ASYMMETRIC CONVECTIVE NETWORK, WITH A SINGLE FRAGMENTED BAND OF DEEP CONVECTION WRAPPING INTO THE CENTER. SURFACE OBSERVATIONS FROM KAGOSHIMA REPORTED A 180 DEGREE WIND SHIFT INDICATIVE OF 16W PASSING OVER THE STATION. THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON EIR, SSMIS AND ANIMATED RADAR IMAGERY AS WELL AS SURFACE OBSERVATIONS. BASED ON 16W BEING OVERLAND, A MAJORITY OF INTENSITY GUIDANCE IS UNAVAILABLE, HOWEVER, KAGOSHIMA AIRPORT WHICH 16W PASSED VERY CLOSE TO REPORTED A STATION PRESSURE OF 963MB AT 181233Z, USING THE KNAFF-ZEHR WIND PRESSURE RELATIONSHIP CORRELATES TO 79-80KTS. THIS COMBINED WITH RJTD DVORAK INTENSITY ESTIMATE OF T4.5 AND THE JTWC INITIAL INTENSITY OF 80 KTS IS ASSESSED WITH HIGH CONFIDENCE. INITIAL WIND RADII BASIS: PERSISTENCE CURRENT STEERING MECHANISM: SUBTROPICAL RIDGE (STR) TO THE EAST AGENCY DVORAK AND AUTOMATED FIXES: PGTW: NO CURRENT ESTIMATE RJTD: T4.5 - 77 KTS CIMSS ADT: 87 KTS AT 180840Z FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: HIGHLY UNFAVORABLE VWS: 15-20 KTS SST: 26-27 CELSIUS OUTFLOW: MODERATE POLEWARD AND EQUATORWARD OTHER FACTORS: LAND INTERACTION WITH JAPAN 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 16W (NANMADOL) IS NOW IN FREE FALL, HAVING MADE LANDFALL OVER SOUTHERN KYUSHU, INTENSITIES WILL RAPIDLY WEAKEN AS 16W ROUNDS THE STR AXIS AND STEADIES UP ON A NORTHEASTERLY HEADING BY TAU 12. THIS IS THE RESULT OF A STRONG COLD FRONT AND MID-LATITUDE TROUGH THAT IS RAPIDLY PULLING DOWN FROM THE NORTHWEST, BREAKING DOWN THE STEERING RIDGE AND FORCING 16W TO EXECUTE A SHARP TURN NORTHEASTWARD. BY TAU 24, 16W WILL INCREASE SPEED TO AROUND 15KTS AND CONTINUE TO WEAKEN. BY TAU 36, 16W WILL BE APPROXIMATELY 45KTS, HAVING SUCCUMB TO INCREASED SHEAR, DRY AIR ENTRAINMENT, AND LAND INTERACTION. SIMILARLY, 16W WILL ALSO BEGIN TO INTERACT WITH THE RAPIDLY APPROACHING FRONTAL SYSTEM THEREBY INITIATING EXTRA-TROPICAL TRANSITION (ETT) AND BY TAU 48 THE SYSTEM WILL BEGIN TO INTEGRATE ITSELF INTO THE SHARP BAROCLINIC ZONE. AFTER TAU 48, THE REMNANTS OF 16W WILL MOVE BACK OVER THE PACIFIC WHERE IT WILL BE ROBBED OF ITS REMAINING TROPICAL CHARACTERISTICS, COMPLETING ETT BY TAU 72. MODEL DISCUSSION: THROUGH TAU 24, NUMERICAL MODELS ARE IN TIGHT AGREEMENT WITH ALL MEMBERS INDICATING A NORTHEASTERLY TURN BY TAU 12. AFTER TAU 24 HOWEVER, ALONG TRACK SPREADING INCREASES AS MODELS ATTEMPT TO RESOLVE PLUMMETING INTENSITIES, LAND INTERACTION AS WELL AS ETT. THERE IS NEARLY A 1000NM SPREAD IN SOLUTIONS, WITH COAMPS-TC AND NVGM SHOWING TERMINATION SHORTLY AFTER EXITING INTO THE PACIFIC WHILE, UKMET AND ITS ENSEMBLE CARRY THE SYSTEM WELL INTO THE NORTH PACIFIC. WHILE THERE IS A HIGH DEGREE OF CONFIDENCE THROUGH TAU 24, THE ABYSMAL SPREAD BY TAU 72 LEADS TO AN OVERALL LOW FORECAST TRACK CONFIDENCE. RELIABLE MODEL INTENSITY GUIDANCE IS IN GOOD AGREEMENT WITH ALL MEMBERS SHOWING SHARP WEAKENING THROUGH THE FORECAST PERIOD, THOUGH DECAY-SHIPS IS MOST AGGRESSIVE, SHOWING A 40KT LOSS IN 24 HOURS. FOR THIS REASON THE JTWC FORECAST INTENSITY IS PLACED WITH MEDIUM CONFIDENCE. FORECAST CONFIDENCE: TRACK 0 - 72 HR: LOW INTENSITY 0 - 72 HR: MEDIUM// NNNN