WDPN32 PGTW 141500 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TYPHOON 25W (VAMCO) WARNING NR 022// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TYPHOON (TY) 25W (VAMCO), LOCATED APPROXIMATELY 68 NM EAST- NORTHEAST OF DA NANG, VIETNAM, HAS TRACKED WEST-NORTHWESTWARD AT 09 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY SHOWS THE SYSTEM CONTINUED TO WEAKEN AS CONVECTIVE TOPS OVER THE 27NM EYEWALL WARMED AND BECAME MORE RAGGED. THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON THE EYE FEATURE IN THE EIR LOOP THAT STACKED UP VERTICALLY WITH THE LOW LEVEL CIRCULATION CENTER DUE TO LOW VERTICAL WIND SHEAR (VWS). THE INITIAL INTENSITY OF 95KTS IS BASED ON AN OVERALL ASSESSMENT OF MULTI-AGENCY DVORAK CURRENT INTENSITY ESTIMATES OF T5.0/90KTS (PGTW AND RCTP) TO T5.5/102 (RJTD), AND REFLECTS THE WEAKENING TREND. UPPER LEVEL ANALYSIS INDICATES FAVORABLE DYNAMICS WITH ROBUST DUAL OUTFLOW AND LOW (05-10KT) VWS; HOWEVER, THE SYSTEM IS DRIFTING OVER COOL (26C) SEA SURFACE TEMPERATURES (SST) AND LOW (<10KJ/CM^2) OCEAN HEAT CONTENT (OHC) THAT ARE OFFSETTING THE FAVORABLE OUTFLOW AND VWS. THE CYCLONE IS TRACKING ALONG THE SOUTHERN PERIPHERY OF A DEEP-LAYERED SUBTROPICAL RIDGE (STR) TO THE NORTHEAST. 3. FORECAST REASONING. A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. TY VAMCO WILL CONTINUE ON ITS WEST-NORTHWESTWARD TRACK UNDER THE STR THROUGHOUT THE FORECAST PERIOD, MAKING LANDFALL OVER CENTRAL VIETNAM NORTHWEST OF HUE SHORTLY AFTER TAU 12. THE SYSTEM WILL CONTINUE TO WEAKEN DUE TO THE LOW SST AND OHC VALUES IN THE SOUTH CHINA SEA APPROACHING VIETNAM, DOWN TO 75KTS BY TAU 12. AFTER LANDFALL, THE RUGGED TERRAIN WILL RAPIDLY ERODE THE SYSTEM DOWN TO 35KTS BY TAU 24, AND DISSIPATE IT BY TAU 36 AFTER IT CROSSES VIETNAM, CENTRAL LAOS, AND INTO THAILAND. NUMERICAL MODELS GRADUALLY AND EVENLY SPREAD OUT TO OVER 220NM BY TAU 36, LENDING HIGH CONFIDENCE IN THE JTWC FORECAST TRACK WHICH IS PLACED NEAR THE THE MULTI-MODEL CONSENSUS.// NNNN