WDPN31 PGTW 222100 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 02W (TWO) WARNING NR 002// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 23.8N 145.3E INITIAL INTENSITY: 30 KTS GEOGRAPHIC REFERENCE: 227 NM EAST-SOUTHEAST OF IWO TO MOVEMENT PAST 6 HOURS: NORTHWESTWARD AT 08 KTS SIGNIFICANT WAVE HEIGHT: 12 FEET SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS A FULLY EXPOSED LOW-LEVEL CIRCULATION CENTER (LLCC) OF TROPICAL DEPRESSION (TD) 02W. TROPICAL UPPER TROPOSPHERIC TROUGH (TUTT) CELL LOCATED TO THE WEST OF THE SYSTEM IS INTRODUCING ELEVATED SHEAR AND RESTRICTING OUTFLOW POTENTIAL. ADDITIONAL ENVIRONMENTAL ANALYSIS REVEALS MARGINALLY FAVORABLE ENVIRONMENT WITH MODERATE POLEWARD AND EASTWARD OUTFLOW ALOFT, LOW TO MODERATE (15-20 KTS) SOUTHWESTERLY VERTICAL WIND SHEAR (VWS) AND WARM (28-29 C) SEA SURFACE TEMPERATURES (SST). WHILE THE LLCC IS EASILY IDENTIFIABLE DUE TO LACK OF CENTRAL CONVECTION, THE ACTIVITY ASSOCIATED WITH THE SPIRAL BANDS WRAPPING INTO THE LLCC HAS PICKED UP OVER THE LAST 2 HOURS. THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE, WHILE THE INITIAL INTENSITY OF 30 KTS IS ASSESSED WITH MEDIUM CONFIDENCE BASED ON THE AGENCY DVORAK AND OBJECTIVE INTENSITY ESTIMATES LISTED BELOW. INITIAL WIND RADII BASIS: NOT APPLICABLE (THERE ARE NO INITIAL WIND RADII). CURRENT STEERING MECHANISM: DEEP-LAYER SUBTROPICAL RIDGE (STR) TO THE NORTHEAST AGENCY DVORAK AND AUTOMATED FIXES: PGTW: T2.0 - 30 KTS RJTD: T1.5 - 25 KTS KNES: T2.0 - 30 KTS CIMSS ADT: 31 KTS AT 221730Z CIMSS AIDT: 35 KTS AT 221730Z CIMSS D-PRINT: 28 KTS AT 221730Z FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: MARGINALLY FAVORABLE VWS: 15-20 KTS SST: 28-29 CELSIUS OUTFLOW: MODERATE POLEWARD AND EASTWARD OTHER FACTORS: TUTT CELL CENTERED TO THE WEST LIMITING THE OUTFLOW ANALYSIS CONFIDENCE: INITIAL POSITION: HIGH INITIAL INTENSITY: MEDIUM INITIAL WIND RADII: NOT APPLICABLE 3. FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO THE FORECAST FROM THE PREVIOUS WARNING. FORECAST DISCUSSION: TD 02W IS FORECAST TO FOLLOW THE WESTERN PERIPHERY OF A DEEP-LAYER STR CURRENTLY LOCATED TO THE NORTHEAST OF THE SYSTEM, WHILE SLOWLY AND STEADILY INTENSIFYING, DUE TO WARM SST. TD 02W IS FORECAST TO REACH PEAK INTENSITY OF 40 KTS WITHIN THE NEXT 24 HOURS, AND MAINTAIN IT FOR ANOTHER DAY. AT THAT POINT, RAPIDLY DECREASING WATER TEMPERATURES, COMBINED WITH REDUCED POLEWARD OUTFLOW, WILL RESULT IN WEAKENING AND BEGINNING OF DISSIPATION AROUND TAU 72, AS THE SYSTEM GETS CLOSER TO YOKOSUKA, JAPAN. SIMULTANEOUSLY, TD 02W WILL ROUND THE AXIS OF THE STR AND START HEADING EAST-NORTHEASTWARD, WHILE FURTHER WEAKENING, WITH FULL DISSIPATION EXPECTED BY TAU 96. MODEL DISCUSSION: NUMERICAL MODEL TRACK GUIDANCE IS IN FAIR AGREEMENT FOR THE INITIAL 72 HOURS, WITH A CROSS-TRACK SPREAD OF 105 NM AT TAU 48, EXPANDING TO 200 NM AT TAU 72. AFTERWARDS, THE GUIDANCE ENVELOPE SHRINKS DOWN TO 65 NM AT THE END OF THE FORECAST PERIOD. THEREFORE THE HIGHEST UNCERTAINTY IS ASSOCIATED WITH THE TIMELINE AND THE LOCATION OF THE RECURVE AXIS, WITH NAVGEM BEING THE PRIMARY OUTLIER AND SUGGESTING THE TRACK AT LEAST 90 NM EAST AND AWAY FROM THE COAST OF JAPAN. SHORT-TERM INTENSITY GUIDANCE IS IN FAIR AGREEMENT, WITH NEARLY ALL MODELS INDICATING STEADY INTENSIFICATION THROUGH TAU 36, FOLLOWED BY WEAKENING. PRIMARY OUTLIERS ARE NAVGEM-DRIVEN COAMPS-TC, WHICH SUGGESTS DISSIPATION WITHIN 36 HOURS, AND HAFS-A, WHICH PREDICTS INTENSIFICATION OVER THE NEXT 96 HOURS, REACHING PEAK INTENSITY OF 55 KTS. THE TRACK GUIDANCE FOR HAFS-A HOWEVER IS TAKING THE SYSTEM MUCH FURTHER WEST AND RECURVING SLOWER THAN THE MULTI-MODEL CONSENSUS. JTWC INTENSITY FORECAST IS THEREFORE ASSESSED CLOSE TO THE CONSENSUS, WITH MEDIUM AND LOW CONFIDENCE, FOR SHORT AND LONG TERM RESPECTIVELY. FORECAST CONFIDENCE: TRACK 0 - 72 HR: MEDIUM TRACK 72-120 HR: MEDIUM INTENSITY 0 - 72 HR: MEDIUM INTENSITY 72-120 HR: LOW// NNNN