MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 23W (MARIA) WARNING NR 15// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TROPICAL STORM 23W (MARIA), LOCATED APPROXIMATELY 490 NM EAST- SOUTHEAST OF TOKYO, JAPAN, HAS TRACKED EAST-NORTHEASTWARD AT 17 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY SHOWS THE LOW LEVEL CIRCULATION CENTER (LLCC) IS BEGINNING TO ELONGATE ALONG THE EAST-WEST AXIS WITH A SMALL FLARE OF CENTRAL CONVECTION IN THE PAST SIX HOURS. UPPER LEVEL ANALYSIS INDICATES THE LLCC IS LOCATED UNDER THE NORTHERN PERIPHERY OF A DEEP LAYERED SUBTROPICAL RIDGE (STR), WHICH IS CREATING STRONG VERTICAL WIND SHEAR (VWS) (25 TO 30 KNOTS) OVER THE LLCC. THE LLCC IS TRACKING ALONG THE NORTHERN PERIPHERY OF THE STR. THE INTENSITY HAS BEEN MAINTAINED AT 45 KNOTS BASED ON THE RECENT INCREASE IN CENTRAL CONVECTION AND A 3.0/3.0 DVORAK FROM PGTW. 3. FORECAST REASONING. A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS PROGNOSTIC REASONING BULLETIN. B. TS MARIA WILL CONTINUE TO TRACK ALONG THE NORTHERN EDGE OF THE STR, WITH DECREASING SURFACE CONDITIONS AND THE PERSISTENT HIGH VWS, CAUSING THE SYSTEM TO RAPIDLY WEAKEN UNTIL THE LLCC IS FULLY DISSIPATED BY TAU 36. NUMERIC GUIDANCE IS IN TIGHT AGREEMENT OVER THE NEXT 24 HOURS THEN WIDELY DIVERGE AFTERWARDS AS MANY OF THE MODELS LOSE THE VORTEX SUPPORTING THE DISSIPATION SCENARIO. THERE IS HIGH CONFIDENCE IN THIS FORECAST.// NNNN NNNN