WDPN31 PGTW 250300 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 25W (MALOU) WARNING NR 005// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 16.1N 138.4E INITIAL INTENSITY: 35 KTS GEOGRAPHIC REFERENCE: 379 NM NORTH OF ULITHI MOVEMENT PAST 6 HOURS: NORTH-NORTHWESTWARD AT 15 KTS SIGNIFICANT WAVE HEIGHT: 14 FEET SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS FORMATIVE BANDING WITH LARGE AREAS OF DEEP SUSTAINED CONVECTION REMAINING WEST AND NORTHEAST OF THE PARTIALLY EXPOSED LOW LEVEL CIRCULATION CENTER. THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED UPON MULTIPLE AGENCY FIXES AND EXTRAPOLATION FROM A BULLSEYE 242226Z ASCAT-A PASS INDICATING MAXIMUM WINDS OF 25-30 KTS. THE INITIAL INTENSITY IS HEDGED SLIGHTLY HIGHER THAN MULTIPLE AGENCY DVORAK ESTIMATES AND SLIGHTLY LOWER THAN THE ADVANCED DVORAK TECHNIQUE. ENVIRONMENTAL CONDITIONS REMAIN FAVORABLE WITH MODERATE POLEWARD AND EQUATORWARD OUTFLOW, LOW VERTICAL WIND SHEAR, AND WARM (29-30C) SEA SURFACE TEMPERATURES. INITIAL WIND RADII BASIS: SCATTEROMETER DATA. 34 KNOT WIND RADII BASED ON THE BULLSEYE 242226Z ASCAT-A PASS. CURRENT STEERING MECHANISM: WESTERN PERIPHERY OF A SUBTROPICAL RIDGE POSITIONED TO THE EAST-NORTHEAST. AGENCY DVORAK AND AUTOMATED FIXES: PGTW: T2.0 - 30 KTS RJTD: T2.0 - 30 KTS KNES: T2.5 - 35 KTS CIMSS SATCON: 42 KTS AT 242217Z CIMSS ADT: 43 KTS AT 250110Z FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE VWS: 10-15 KTS SST: 29-30 CELSIUS OUTFLOW: MODERATE RADIAL ANALYSIS CONFIDENCE: INITIAL POSITION: HIGH INITIAL INTENSITY: MEDIUM INITIAL WIND RADII: MEDIUM 3. FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO THE FORECAST FROM THE PREVIOUS WARNING. FORECAST DISCUSSION: TROPICAL STORM MALOU IS FORECAST TO TRACK NORTH-NORTHWESTWARD OVER THE NEXT 24-36 HOURS UNDER THE INFLUENCE OF THE SUBTROPICAL RIDGE TO THE EAST-NORTHEAST. SHORTLY AFTER TAU 48, THE SYSTEM WILL BEGIN ROUNDING THE SUBTROPICAL RIDGE AXIS, MAKE A TURN TO THE NORTH-NORTHEAST, AND THEN INCREASE INTENSITY TO TYPHOON STRENGTH. TS MALOU WILL REMAIN IN A FAVORABLE ENVIRONMENT REACHING A PEAK INTENSITY OF 80 KTS THROUGH TAU 96. THEREAFTER, THE SYSTEM WILL BEGIN ENCOUNTERING COOLING SEA SURFACE TEMPERATURES, INCREASED VERTICAL WIND SHEAR AS IT MOVES THROUGH THE MID-LATITUDE WESTERLIES, AND BEGINS TRANSITIONING INTO AN EXTRATROPICAL LOW PRESSURE SYSTEM. MODEL DISCUSSION: NUMERICAL MODEL GUIDANCE IS IN GOOD AGREEMENT IN REGARDS TO THE FORECAST TRACK FOR TS 25W, WITH ALMOST ALL MODELS CONTINUING TO SHOW A GENERALLY NORTH-NORTHWESTWARD TRACK FOLLOWED BY A RECURVE TO THE NORTHEAST STARTING AT TAU 48. NVGM IS STILL THE MAJOR OUTLIER OF THE MULTIPLE MODEL CONSENSUS. EXCLUDING NVGM, CROSS-TRACK MODEL SPREAD IS LESS THAN 120 NM ALL THE WAY UP TO TAU 72. NUMERICAL MODEL GUIDANCE IS IN MODERATE AGREEMENT IN REGARDS TO THE INTENSITY FORECAST, WITH MOST MODELS INDICATING A STEADY INTENSIFICATION WITH A PEAK INTENSITY BETWEEN TAUS 72 AND 96. THEREAFTER, A WEAKENING TREND IS EXPECTED THROUGH THE REMAINDER OF THE FORECAST. THE MODELS CURRENTLY DO NOT AGREE ON THE PEAK INTENSITY WITH HWRF PEAKING AT 100 KTS AND GFS PEAKING AT 70 KTS, WITH MOST OTHERS AROUND 70-90 KTS. TO OFFSET HWRF, THE FORECAST INTENSITY IS PLACED SLIGHTLY LOWER THAN CONSENSUS. FORECAST CONFIDENCE: TRACK 0 - 72 HR: HIGH TRACK 72 - 120 HR: LOW INTENSITY 0 - 72 HR: MEDIUM INTENSITY 72 - 120 HR: LOW// NNNN