MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 03W (HAGUPIT) WARNING NR 005// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TROPICAL STORM (TS) 03W (HAGUPIT), LOCATED APPROXIMATELY 279 NM SOUTHWEST OF KADENA AB, OKINAWA, HAS TRACKED WEST-NORTHWESTWARD AT 12 KNOTS (KTS) OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY, ALONG WITH RADAR IMAGERY FROM THE MIYAKOJIMA/YAEYAMA RADAR, DEPICTS CONVECTIVE BANDING WRAPPING TIGHTLY INTO A WELL-DEFINED LOW LEVEL CIRCULATION CENTER (LLCC). A 012237Z COMPOSITE MICROWAVE IMAGE SHOWS FRAGMENTED DEEP CONVECTION TO THE EAST OF THE DISTINCT LLCC. THEREFORE, THE INITIAL POSITION IS PLACED WITH GOOD CONFIDENCE. THE INTENSITY REMAINS ASSESSED AT 35 KTS, SUPPORTED BY A 012355Z PARTIAL ASCAT-A PASS SHOWING A SWATH OF 30-35 KT WINDS IN THE NORTHEAST QUADRANT AND DVORAK CURRENT INTENSITY ESTIMATES OF T2.0-2.5 (30-35 KTS) BY PGTW/RJTD. WIND RADII HAVE BEEN UPDATED WITH THE MOST RECENT ASCAT DATA. ENVIRONMENTAL ANALYSIS REVEALS ESTABLISHED UPPER LEVEL OUTFLOW AND WARM (>30 CELSIUS) SEA SURFACE TEMPERATURES. HOWEVER, MODERATE (15-20 KT) NORTHERLY VERTICAL WIND SHEAR CONTINUES TO IMPACT CONVECTION OVER THE WESTERN SEMICIRCLE. OVERALL, THE ENVIRONMENT REMAINS CONDUCIVE FOR CONTINUED DEVELOPMENT. A DEEP-LAYERED SUBTROPICAL RIDGE (STR) LOCATED TO THE NORTH WILL ACT AS THE PRIMARY STEERING INFLUENCE AS TS 03W TRACKS POLEWARD AROUND ITS PERIPHERY. 3. FORECAST REASONING. A. NO CHANGE IN THE FORECAST PHILOSOPHY SINCE THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. TS 03W IS FORECAST TO TRACK NORTH-NORTHWESTWARD ALONG THE PERIPHERY OF THE STR, MAKING LANDFALL SOUTH OF THE SHANGHAI REGION PRIOR TO TAU 48. ALONG THIS TRACK, THE SYSTEM WILL CONTINUE TO INTENSIFY TO A PEAK OF 45 KTS BY TAU 24. DUE TO THE COMPACT NATURE OF THIS SYSTEM, THERE IS POTENTIAL FOR A HIGHER PEAK INTENSITY. FOLLOWING THIS, INCREASING NORTHERLY VWS IS EXPECTED TO HINDER ADDITIONAL INTENSIFICATION AND BEGIN TO WEAKEN THE SYSTEM. AFTER TAU 48, TS 03W WILL TURN TO A NORTHWARD COURSE AS IT ROUNDS THE STR AXIS AND BEGINS TO RECURVE TO THE NORTHEAST. THE SYSTEM IS ANTICIPATED TO INTERACT WITH THE MID-LATITUDE WESTERLIES AROUND TAU 72 AND COMMENCE EXTRATROPICAL TRANSITION (ETT). NUMERICAL MODEL GUIDANCE IS IN TIGHT AGREEMENT THROUGH TAU 48. AFTERWARDS, THERE IS VARIATION IN THE TIMING OF THE RECURVE WHICH INCREASES THE SPREAD BETWEEN MODEL SOLUTIONS. C. TS 03W WILL CONTINUE TO WEAKEN AS IT REEMERGES OVER THE COOL WATERS (22-23 CELSIUS) NORTH OF THE SHANGHAI REGION. THE SYSTEM IS FORECAST TO TRANSIT NORTHEASTWARD WHILE IT COMPLETES ETT BY TAU 96, IF NOT SOONER. DUE TO AN OVERALL UNFAVORABLE ENVIRONMENTAL CONDITIONS, THE SYSTEM MAY DISSIPATE PRIOR TO ETT COMPLETION. POSITIONED NEAR THE MULTI-MODEL CONSENSUS, THERE IS MODERATE CONFIDENCE IN THE JTWC FORECAST TRACK.// NNNN NNNN