WDPN31 PGTW 220300 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 22W (TRAMI) WARNING NR 007// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 13.6N 127.4E INITIAL INTENSITY: 35 KTS GEOGRAPHIC REFERENCE: 377 NM EAST OF MANILA, PHILIPPINES MOVEMENT PAST 6 HOURS: NORTHWESTWARD AT 09 KTS SIGNIFICANT WAVE HEIGHT: 22 FEET SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS TROPICAL STORM 22W (TRAMI) AS IT CONTINUES DEVELOPING SPIRAL BANDS OF DEEP CONVECTION WRAPPING INTO A PARTLY EXPOSED LOW-LEVEL CIRCULATION CENTER, JUST EAST OF LUZON, PHILIPPINES. FLARING CONVECTION AND STRONG POLEWARD AND EQUATORWARD OUTFLOW ARE FUELING STEADY DEVELOPMENT AS THE SYSTEM TRACKS NORTHWESTWARD. THE INITIAL POSITION IS PLACED WITH MEDIUM CONFIDENCE BASED ON THE PARTLY EXPOSED LLCC IN THE ANIMATED MSI, AS WELL AS AN ARC FEATURE IN THE 212123Z SSMIS 37 GHZ IMAGE. THE INITIAL INTENSITY OF 35 KTS IS ASSESSED WITH MEDIUM CONFIDENCE BASED ON THE OBJECTIVE AND AGENCY ESTIMATES LISTED BELOW AND REFLECTS THE MOSTLY SUSTAINED 6-HR CONVECTIVE AND WRAP SIGNATURES. INITIAL WIND RADII BASIS: PERSISTENCE CURRENT STEERING MECHANISM: SOUTHWEST EXTENSION OF THE SUBTROPICAL RIDGE (STR) TO THE NORTHEAST AGENCY DVORAK AND AUTOMATED FIXES: PGTW: T2.5 - 35 KTS RJTD: T2.0 - 30 KTS RCTP: T2.5 - 35 KTS KNES: T2.5 - 35 KTS CIMSS SATCON: 45 KTS AT 212139Z CIMSS ADT: 39 KTS AT 212330Z CIMSS DPRNT: 34 KTS AT 220000Z FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: MARGINALLY FAVORABLE VWS: 20-25 KTS SST: 29-30 CELSIUS OUTFLOW: STRONG POLEWARD AND EQUATORWARD 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 TRAMI WILL CONTINUE TRANSITING NORTHWESTWARD OVER THE NEXT 36 HOURS UNDER THE INFLUENCE OF THE STR EXTENSION TO THE NORTHEAST. AS THE SYSTEM APPROACHES LUZON, ANOTHER STR TO THE NORTH WILL ASSUME THE STEERING AND LEAD TRAMI WESTWARD INTO LUZON, WHILE THE SYSTEM REACHES 50 KTS PRIOR TO LANDFALL IN THE PHILIPPINES. AS TS 22W MOVES WESTWARD ACROSS THE CORDILLERA MOUNTAIN RANGE, THE TERRAIN INTERACTION WILL LEAD TO SLIGHT WEAKENING, FOLLOWED BY STEADY INTENSIFICATION DRIVEN BY HIGH SEA SURFACE TEMPERATURES AND OCEAN HEAT CONTENT AFTER IT EXITS INTO THE SOUTH CHINA SEA, OFFSET ONLY BY COOLING SEA SURFACE TEMPERATURES. THE SYSTEM IS FORECAST TO REACH PEAK INTENSITY OF 60 KTS BY TAU 96, AFTER WHICH IT WILL START WEAKENING DUE TO LAND INTERACTION AS IT APPROACHES HAINAN AND SOUTH CHINA, AS WELL AS A NORTHEASTERLY WIND SURGE BRINGING COLD AND DRY AIR INTO THE SYSTEM. MODEL DISCUSSION: DETERMINISTIC MODEL GUIDANCE IS IN GOOD AGREEMENT THROUGHOUT THE INITIAL 72 HOURS, WITH 70NM CROSS-TRACK SPREAD PRIOR TO LUZON LANDFALL. THE TRACK GUIDANCE PAST THAT IS SLIGHTLY LESS CONSISTENT WITH GFS TAKING THE MOST SOUTHERN ROUTE, OFFSET BY NAVGEM ON THE NORTHERN SIDE, WITH A CROSS-TRACK SPREAD OF OVER 200 NM. JTWC TRACK FORECAST IS PLACED CLOSE TO THE MULTI-MODEL CONSENSUS, SLIGHTLY CLOSER TO THE SOUTHERN TRACKS. INTENSITY GUIDANCE IS IN FAIR AGREEMENT AND THE JTWC FORECAST IS PLACED ON THE HIGHER SIDE OF THE MULTI-MODEL CONSENSUS, CLOSER TO THE GFS GUIDANCE, WITH A PEAK INTENSITY OF 60 KTS BY TAU 96. FORECAST CONFIDENCE: TRACK 0 - 72 HR: HIGH TRACK 72-120 HR: MEDIUM INTENSITY 0 - 72 HR: MEDIUM INTENSITY 72-120 HR: MEDIUM// NNNN