WDPN31 PGTW 021500 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 10W (SAOLA) WARNING NR 23// RMKS// 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TROPICAL STORM (TS) 10W (SAOLA), LOCATED APPROXIMATELY 40 NM NORTH-NORTHWEST OF TAIPEI, TAIWAN, HAS TRACKED NORTH-NORTHWESTWARD AT 06 KNOTS OVER THE PAST SIX HOURS. ANIMATED INFRARED SATELLITE IMAGERY SHOWS THE SYSTEM HAS REGAINED SOME CONVECTIVE BANDING AS IT MOVED OFFSHORE FROM NORTHERN TAIWAN INTO THE TAIWAN STRAIT. A RADAR REFLECTIVITY LOOP FROM THE TAIWAN CENTRAL WEATHER BUREAU INDICATES THE LOW LEVEL CIRCULATION CENTER HAS REMAINED INTACT AND LENDS GOOD CONFIDENCE TO THE INITIAL POSITION. THE INITIAL INTENSITY IS BASED ON THE DVORAK ESTIMATE FROM KNES. UPPER LEVEL ANALYSIS INDICATES THE SYSTEM IS JUST TO THE WEST OF A RIDGE AXIS IN AN AREA OF LIGHT (05-10 KNOT) VERTICAL WIND SHEAR. ANIMATED WATER VAPOR IMAGERY SHOWS GOOD EQUATORWARD OUTFLOW AS THE SYSTEM HAS BECOME MORE COMPACT. THE CYCLONE IS TRACKING ALONG THE SOUTHWESTERN PERIPHERY OF A DEEP- LAYERED SUBTROPICAL RIDGE (STR) CENTERED OVER HONSHU, JAPAN. 3. FORECAST REASONING. A. THERE IS NO SIGNIFICANT CHANGE TO THE FORECAST PHILOSOPHY FROM THE PREVIOUS PROGNOSTIC REASONING. B. TS 10W IS EXPECTED TO ACCELERATE NORTHWESTWARD AND SLIGHTLY INTENSIFY AS IT DRIFTS ACROSS THE TAIWAN STRAIT BEFORE IT MAKES LANDFALL NEAR FUZHOU, CHINA BEFORE TAU 12. DYNAMIC MODEL GUIDANCE IS IN TIGHT AGREEMENT AND SUPPORTS THE HIGH CONFIDENCE FORECAST TRACK. TS SAOLA IS EXPECTED TO DISSIPATE AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND BY TAU 36. // NNNN