WDPN31 PGTW 291500 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 06W (JANGMI) WARNING NR 010// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 16.5N 131.7E INITIAL INTENSITY: 45 KTS GEOGRAPHIC REFERENCE: 638 NM SOUTH-SOUTHEAST OF KADENA AB MOVEMENT PAST 6 HOURS: WEST-NORTHWESTWARD AT 12 KTS SIGNIFICANT WAVE HEIGHT: 23 FEET SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS SIGNIFICANTLY IMPROVED CONVECTIVE SIGNATURE ASSOCIATED WITH TROPICAL STORM (TS) 06W (JANGMI). INITIAL POSITION IS ASSESSED WITH HIGH CONFIDENCE BASED ON A 291112 GPM GMI 37 GHZ MICROWAVE IMAGERY DEPICTING A CONTINUOUSLY BROAD LOW-LEVEL CIRCULATION CENTER (LLCC) WITH NEARLY ALL OF THE DEEP CONVECTION CONCENTRATED IN THE SOUTHERN SEMICIRCLE. THE AMBIENT THERMODYNAMIC AND KINEMATIC ENVIRONMENT IS LARGELY CONDUCIVE FOR CONTINUED CYCLOGENESIS, HIGHLIGHTED BY ELEVATED SEA SURFACE TEMPERATURES OF 29-30 C AND MODERATE EQUATORWARD OUTFLOW ALOFT. HOWEVER, ANALYSIS OF WATER VAPOR AND SHORTWAVE INFRARED IMAGERY REVEALS COMPETING MITIGATING FACTORS, SPECIFICALLY THE PRESENCE OF MID-LEVEL DRY AIR ENTRAINMENT AND PERSISTENT NORTHEASTERLY VERTICAL WIND SHEAR (10-15 KTS) IMPINGING ON THE NORTHEASTERN QUADRANT. THE INITIAL INTENSITY IS ASSESSED AT 45 KTS WITH HIGH CERTAINTY, A VALUE CONSISTENT WITH SUBJECTIVE AGENCY DVORAK ESTIMATES AND AUTOMATED OBJECTIVE AIDS LISTED BELOW AND SUPPORTED BY RECENTLY EXPANDED CONVECTIVE ACTIVITY. INITIAL WIND RADII BASIS: PERSISTENCE CURRENT STEERING MECHANISM: SUBTROPICAL RIDGE CENTERED TO THE NORTHEAST AGENCY DVORAK AND AUTOMATED FIXES: PGTW: T3.0 - 45 KTS RJTD: T2.5 - 35 KTS RCTP: T3.0 - 45 KTS KNES: T3.0 - 45 KTS CIMSS SATCON: 47 KTS AT 291200Z CIMSS ADT: 37 KTS AT 291200Z CIMSS AIDT: 34 KTS AT 291200Z CIMSS D-MINT: 48 KTS AT 290841Z CIMSS D-PRINT: 41 KTS AT 291200Z FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE VWS: 10-15 KTS SST: 29-30 CELSIUS OUTFLOW: MODERATE 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: TS 06W IS FORECAST TO CONTINUE TRANSITING ALONG THE SOUTHWESTERN PERIPHERY OF A BUILDING SUBTROPICAL RIDGE (STR) CENTERED TO THE NORTHEAST OVER THE NEXT 48 HOURS. DURING THAT TIME, THE MID-LEVEL NORTHEASTERLY VERTICAL WIND SHEAR (VWS) IS EXPECTED TO RELAX, WHICH WILL ALLOW THE SYSTEM TO FURTHER CONSOLIDATE AND INTENSIFY. PEAK INTENSITY OF 80 KTS IS EXPECTED AROUND TAU 48. AFTER THAT, THE SYSTEM IS EXPECTED TO REACH THE AXIS OF THE RIDGE AND BEGIN POLEWARD AND EVENTUALLY EASTWARD TURN. AS THE GUIDANCE HAVE BEEN SHIFTING SLIGHTLY WESTWARD, THE TRACK IS NOW EXPECTED TO OVERLAY THE WARM WATER SIGNATURE OF THE KUROSHIO CURRENT UNDERNEATH. AS SUCH, THE WEAKENING IMPACTED BY OTHERWISE COOLING SEA SURFACE TEMPERATURES WILL BE SLIGHTLY REDUCED, ALLOWING THE SYSTEM TO MAINTAIN MAXIMUM WIND SPEEDS OF 55-60 KTS AROUND THE TIME TS JANGMI APPROACHES THE ISLAND OF KYUSHU. BEYOND TAU 96, AS THE SYSTEM ACCELERATES NORTHEASTWARD, REDUCED OCEANIC HEAT CONTENT WILL LIKELY INDUCE LOCALIZED COLD WAKE UPWELLING, THEREBY ACCELERATING VORTEX DECAY. AT THE SAME TIME, THE SYSTEM WILL BEGIN INTERACTING WITH THE MID-LATITUDE WESTERLIES. WHILE THE INTRODUCTION OF BAROCLINIC FORCING IMPACTS IS EXPECTED TO ENHANCE POLEWARD VENTILATION VIA THE JET STREAM, THESE DYNAMIC BENEFITS WILL BE RAPIDLY OVERWHELMED BY A HOSTILE THERMODYNAMIC BOUNDARY LAYER CHARACTERIZED BY PLUMMETING SEA SURFACE TEMPERATURES AND INCREASING VWS. CONSEQUENTLY, A PRECIPITOUS WEAKENING TREND WILL COMMENCE, ACCOMPANIED BY A SIGNIFICANT KINEMATIC EXPANSION OF THE WIND FIELD, POSING POTENTIAL HAZARDS TO MAINLAND JAPAN. MODEL DISCUSSION: NUMERICAL MODEL TRACK GUIDANCE, ENCOMPASSING BOTH DYNAMICAL SUITES AND EXPERIMENTAL AI MODELS, UNANIMOUSLY AGREES ON A RECURVATURE SCENARIO DICTATED BY THE NORTHEASTERN SUBTROPICAL RIDGE. WHILE THE CONFIDENCE IN THE SHORT-TERM REMAINS HIGH, LONG-TERM PREDICTION IS LAID WITH MEDIUM CONFIDENCE. NAVGEM REMAINS THE PRIMARY OUTLIER, OFFERING THE WIDEST TURN WITH PORTION OF THE GUIDANCE SUGGESTING TS 06W TRANSITING AS FAR WEST AS ISHIGAKIJIMA. ADDITIONALLY, NAVGEM REMAINS THE SLOWEST SOLUTION, SIGNIFICANTLY INCREASING ALONG-TRACK SPREAD OF THE CONSENSUS GUIDANCE ENVELOPE. THE CROSS-TRACK SPREAD AROUND THE CPA TO KADENA IS CURRENTLY ESTIMATED AT 50 NM WITH NAVGEM EXCLUDED, AND 120 NM ACROSS ALL MODELS. CONVERSELY, THE ALONG-TRACK SPREAD AT TAU 120 INCLUDING NAVGEM IS CURRENTLY ESTIMATED AT NEARLY 650 NM, REDUCED TO 300 NM BY REMOVING NAVGEM FROM THE ESTIMATION. OF NOTE, ADDITION OF ALL AVAILABLE EXPERIMENTAL AI MODELS INCREASES THE ALONG-TRACK SPREAD TO JUST 320 NM. AS SUCH, JTWC OFFICIAL TRACK FORECAST IS PLACED CLOSE TO THE MULTI-MODEL CONSENSUS PREDICTION, OFFSET FOR THE IMPACTS OF THE ONLY REMAINING OUTLIER - NAVGEM. REGARDING INTENSITY GUIDANCE, CONFIDENCE IS SIMILARLY MEDIUM. WHILE ALL CONSENSUS MEMBERS AGREE ON THE TEMPORAL EVOLUTION - PEAKING BETWEEN TAU 48 AND 72 FOLLOWED BY ACCELERATED DECAY, SIGNIFICANT AMPLITUDE DISPERSION PERSISTS. THE DETERMINISTIC GFS ESTABLISHES THE UPPER BOUND AT 105-110 KTS, WHILE STATISTICAL-DYNAMICAL MODELS, AS WELL AS MESOSCALE HAFS, PREDICT MAXIMUM INTENSITY AT OR JUST UNDER 80 KTS. THE OFFICIAL JTWC INTENSITY FORECAST IS ALIGNED SLIGHTLY ABOVE THE MULTI-MODEL CONSENSUS MEAN, BUT REMAINING ON THE MORE CONSERVATIVE OF THE FULL GUIDANCE SPREAD. FORECAST CONFIDENCE: TRACK 00-72 HR: HIGH TRACK 72-120 HR: MEDIUM INTENSITY 00-72 HR: MEDIUM INTENSITY 72-120 HR: MEDIUM// NNNN