WDPN32 PGTW 262100 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TYPHOON 21W (MOLAVE) WARNING NR 012// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TYPHOON 21W (MOLAVE), LOCATED APPROXIMATELY 472 NM EAST- SOUTHEAST OF DA NANG, VIETNAM, HAS TRACKED WESTWARD AT 18 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS A STRENGTHENING SYSTEM WITH A TRANSIENT EYE THAT HAS BEGUN TO REFORM STARTING 1900Z. THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON THE REFORMATION OF THE EYE FEATURE IN THE EIR LOOP AND THE MICROWAVE EYE FEATURE PRESENT IN A 261830Z ATMS 165.5 GHZ IMAGE. THE INITIAL INTENSITY OF 90 KTS IS ALSO PLACED WITH HIGH CONFIDENCE AND IS BASED ON A PGTW DVORAK CURRENT INTENSITY ESTIMATE OF T5.0 (90 KTS). TY MOLAVE CONTINUES TO TRACK UNDER THE STEERING INFLUENCE OF A SUBTROPICAL RIDGE (STR) POSITIONED TO THE NORTH AND THROUGH AN ENVIRONMENT THAT IS MARGINALLY FAVORABLE FOR FURTHER DEVELOPMENT WITH WARM (29-30 CELSIUS) SEA SURFACE TEMPERATURES (SST) AND WELL ESTABLISHED EQUATORWARD AND WESTWARD OUTFLOW ALOFT OFFSET BY CONVERGENT UPPER LEVEL FLOW ALONG THE NORTHERN PERIPHERY OF THE SYSTEM AND MODERATE (20-25 KTS) VERTICAL WIND SHEAR (VWS). 3. FORECAST REASONING. A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. TY MOLAVE IS FORECAST TO CONTINUE TRACKING WEST TO WEST- NORTHWESTWARD THROUGH THE REMAINDER OF THE FORECAST PERIOD UNDER THE STEERING INFLUENCE OF THE DEEP-LAYER STR OVER SOUTHERN CHINA. THE SYSTEM IS EXPECTED TO CONTINUE TO INTENSIFY TO A PEAK OF 100 KNOTS IN THE NEXT 12 HOURS, LARGELY DUE TO FAVORABLE SSTS, WEAKENING VWS (10-15 KTS BY TAU 12) AND IMPROVED UPPER LEVEL OUTFLOW. AFTER TAU 12, THE ENVIRONMENT WILL BECOME LESS FAVORABLE AS VWS INCREASES TO 20-25 KTS BY TAU 24, LEADING TO A SUSTAINED INTENSITY OF 100 KTS BY TAU 24. BETWEEN TAU 24 AND TAU 36, COOLING SSTS AND CONTINUED MARGINAL VWS WILL LEAD TO A GRADUAL WEAKENING BEFORE LANDFALL AT TAU 36 SOUTH OF DA NANG, VIETNAM. BY THIS TIME, TY MOLAVE WILL BEGIN TO DISSIPATE OVER LAND AND WEAKEN TO 65 KTS DUE TO INTERACTION WITH THE UNDERLYING TERRAIN OF VIETNAM AND INCREASING VWS. THE SYSTEM IS THEREAFTER FORECAST TO CONTINUE TO DISSIPATE OVER LAND AS IT TRACKS THROUGH LAOS AND INTO THAILAND, WHEREUPON IT WILL DISSIPATE OVER LAND BY TAU 72. NUMERICAL MODEL TRACK GUIDANCE IS IN TIGHT AGREEMENT FOR THE ENTIRE 72 HOUR FORECAST PERIOD WITH A MAXIMUM SPREAD IN MODEL TRACKS OF 140 NM BY TAU 72. MODEL INTENSITY GUIDANCE CONTINUES TO DIVERGE IN THE NEAR TERM WITH A WEAKENING TREND PREDICTED BY GFS DRIVEN GLOBAL AND MESOSCALE MODELS, AND A GRADUAL INTENSIFICATION PREDICTED THROUGH TAUS 12-24 BY COAMPS AND STATISTICAL-DYNAMICAL MODELS. OVERALL, THE TIGHT AGREEMENT IN NUMERICAL MODEL GUIDANCE LENDS HIGH CONFIDENCE IN THE JTWC FORECAST TRACK, WHICH IS PLACED ALONG THE JTWC MULTI- MODEL CONSENSUS.// NNNN