MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR SUPER TYPHOON 09W (RAMMASUN) WARNING NR 32// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUPER TYPHOON 09W (RAMMASUN), LOCATED APPROXIMATELY 220 NM SOUTHWEST OF HONG KONG, HAS TRACKED WEST-NORTHWESTWARD AT 12 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL (MSI) AND ENHANCED INFRARED SATELLITE IMAGERY SHOW THE EYE HAS IMPROVED ORGANIZATION WITH A SMALL INCREASE IN COLD CLOUD TOPS. AS THE DVORAK INTENSITY ESTIMATES HAVE INCREASED OVER THE PAST SIX HOURS AND THERE IS EVIDENCE OF IMPROVEMENTS IN THE STRUCTURE, THE INTENSITY HAS BEEN INCREASED TO 135 KNOTS. UPPER LEVEL ANALYSIS SHOWS A FAVORABLE ENVIRONMENT CHARACTERIZED BY STRONG EQUATORWARD OUTFLOW AND MODERATE (15 TO 20 KNOTS) VERTICAL WIND SHEAR. THE INITIAL POSITION IS BASED UPON THE DEFINED EYE FEATURE IN THE MSI LOOP WITH HIGH CONFIDENCE. STY 09W IS STEADILY TRACKING WEST-NORTHWEST ALONG THE SOUTHWESTERN PERIPHERY OF THE SUBTROPICAL RIDGE (STR) EXTENDING OVER EASTERN CHINA. 3. FORECAST REASONING. A. NO CHANGE TO FORECAST PHILOSOPHY SINCE THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. STY 09W IS FORECAST TO REMAIN ON A GENERALLY WEST- NORTHWESTWARD TRACK AS THE STR PERSISTS TO INFLUENCE THE TRACK FOR THE REMAINDER OF THE FORECAST. STY 09W IS EXPECTED TO BEGIN TO WEAKEN AS THE STORM CONTINUES TO TRACK ACROSS HAINAN AND THE LUICHOW PENINSULA OVER THE NEXT 6 HOURS. BETWEEN TAU 12 AND 24, STY RAMMASUN WILL MAKE FINAL LANDFALL IN NORTHERN VIETNAM, WHICH WILL CAUSE RAPID WEAKENING DUE TO FRICTIONAL EFFECTS OF THE NORTHERN MIDLANDS AND MOUNTAINOUS REGION WITH COMPLETE DISSIPATION OF THE SYSTEM IS EXPECTED BY TAU 48. NUMERIC MODEL GUIDANCE IS IN VERY TIGHT AGREEMENT WITH THE TRACK FORECAST, WHICH IS POSITIONED WITH HIGH CONFIDENCE.// NNNN NNNN