WDPN32 PGTW 102100 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 13W (PEILOU) WARNING NR 016// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 22.4N 154.1E INITIAL INTENSITY: 35 KTS GEOGRAPHIC REFERENCE: 725 NM WEST-NORTHWEST OF WAKE ISLAND MOVEMENT PAST 6 HOURS: NORTHEASTWARD AT 14 KTS SIGNIFICANT WAVE HEIGHT: 15 FEET SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS PERSISTENT CONVECTION OVER THE LOW-LEVEL CIRCULATION CENTER OVER THE PAST 6 HOURS, HOWEVER, A BRIEF GLIMPSE OF LOW-LEVEL CLOUD BANDS EXPOSED IN THE SOUTHEASTERN QUADRANT REVEALED APPARENT SOUTHEASTERLY SHEAR. A 101524 89 GHZ AMSR-2 MICROWAVE IMAGE CONFIRMED THIS STRUCTURAL OFFSET. A 101404Z OCEANSAT-3 WIND SPEED PRODUCT CONFIRMED 30-35 KT WINDS PERSISTING IN THE SOUTHERN SEMICIRCLE. THE INITIAL POSITION IS PLACED WITH MEDIUM CONFIDENCE BASED ON EXTRAPOLATION FROM THE AMSR-2 IMAGERY AND THE ANIMATED EIR IMAGERY. THE INITIAL INTENSITY OF 35 KTS IS ASSESSED WITH MEDIUM CONFIDENCE BASED ON THE SCATTEROMETRY DATA, DESPITE BEING WELL BELOW THE AGENCY FIXES AND CIMSS OBJECTIVE INTENSITY ESTIMATES. THE ENVIRONMENT IS CHARACTERIZED AS MARGINAL WITH HIGH SEA SURFACE TEMPERATURES BEING OFFSET BY WEAK OUTFLOW ALOFT. INITIAL WIND RADII BASIS: PERSISTENCE CURRENT STEERING MECHANISM: EASTERN PERIPHERY OF A LARGE, LOW-LEVEL CYCLONIC GYRE CENTERED TO THE WEST. AGENCY DVORAK AND AUTOMATED FIXES: PGTW: T2.5 - 35 KTS RJTD: T2.5 - 35 KTS RCTP: T3.0 - 45 KTS KNES: T2.5 - 35 KTS CIMSS SATCON: 47 KTS AT 101800Z CIMSS ADT: 51 KTS AT 101800Z CIMSS AIDT: 40 KTS AT 101800Z CIMSS D-MINT: 45 KTS AT 101549Z CIMSS D-PRINT: 54 KTS AT 101800Z FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: MARGINAL VWS: 5-10 KTS SST: 28-29 CELSIUS OUTFLOW: WEAK POLEWARD ANALYSIS CONFIDENCE: INITIAL POSITION: MEDIUM INITIAL INTENSITY: MEDIUM INITIAL WIND RADII: LOW 3. FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO THE FORECAST FROM THE PREVIOUS WARNING. FORECAST DISCUSSION: TROPICAL STORM (TS) 13W (PEILOU) IS FORECAST TO CONTINUE ON A NORTHEASTWARD TRACK EMBEDDED IN THE SOUTHWESTERLY MONSOON FLOW ON THE EASTERN EDGE OF THE BROAD CYCLONIC GYRE SITUATED TO THE WEST. AFTER TAU 36 THE TRACK TURNS EAST-NORTHEASTWARD UNDER THE INFLUENCE OF A SEPARATE SUBTROPICAL RIDGE BUILDING IN FROM THE EAST. THE INTENSITY IS FORECAST TO GRADUALLY WEAKEN THROUGHOUT THE FORECAST PERIOD AS THE SYSTEM ENTERS A DRIER ENVIRONMENT AND EVENTUALLY MOVES INTO A HIGHER SHEAR ENVIRONMENT. THE SYSTEM IS EXPECTED TO DISSIPATE OVER WATER BY TAU 48. MODEL DISCUSSION: MODEL TRACK GUIDANCE IS IN GOOD AGREEMENT ABOUT THE NORTHEASTWARD TRACK AND THE JTWC TRACK FORECAST IS PLACED NEAR THE MULTI-MODEL CONSENSUS WITH HIGH CONFIDENCE. WITH THE EXCEPTION OF SHIPS SOLUTIONS, MODEL INTENSITY GUIDANCE AGREES ON AN OVERALL WEAKENING TREND AND DISSIPATION. THE JTWC INTENSITY FORECAST IS PLACED ON THE LOWER END OF THE GUIDANCE ENVELOPE WITH MEDIUM CONFIDENCE TO ACCOUNT FOR THE SHIPS OUTLIERS. FORECAST CONFIDENCE: TRACK 00-72 HR: HIGH INTENSITY 00-72 HR: MEDIUM// NNNN