WDPN32 PGTW 242100 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 21W (MOLAVE) WARNING NR 004// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TROPICAL STORM (TS) 21W (MOLAVE), LOCATED APPROXIMATELY 401 NM EAST OF MANILA, PHILIPPINES, HAS TRACKED WESTWARD AT 11 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY DEPICTS A CONSOLIDATING SYSTEM WITH IMPROVED CONVECTIVE BANDING WRAPPING INTO THE LOW LEVEL CIRCULATION CENTER (LLCC). A 242011Z SSMIS 91GHZ MICROWAVE IMAGE INDICATES TIGHTLY-CURVED BANDING WRAPPING INTO THE LLCC, WHICH SUPPORTS THE INITIAL POSITION WITH GOOD CONFIDENCE; THE 37GHZ IMAGE DEPICTS A SMALL MICROWAVE EYE FEATURE, WHICH TYPICALLY SIGNALS RAPID INTENSIFICATION ONSET. THE INITIAL INTENSITY REMAINS ASSESSED AT 35 KNOTS BASED ON THE HIGHER END OF DVORAK INTENSITY ESTIMATES RANGING FROM T2.0-2.5 (30-35 KNOTS). UPPER-LEVEL ANALYSIS REVEALS A FAVORABLE ENVIRONMENT WITH LOW-MODERATE (15-20 KTS) VERTICAL WIND SHEAR (VWS), IMPROVING POLEWARD OUTFLOW AND GOOD EQUATORWARD OUTFLOW. SST VALUES (30C) AND OCEAN HEAT CONTENT VALUES REMAIN VERY CONDUCIVE FOR FURTHER DEVELOPMENT. TS 21W IS TRACKING GENERALLY WESTWARD UNDER THE STEERING INFLUENCE OF A SUBTROPICAL RIDGE (STR) POSITIONED TO THE NORTHEAST WITH AN EXTENSION TO THE NORTH. 3. FORECAST REASONING. A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. TS 21W IS EXPECTED TO CONTINUE CONSOLIDATING AS IT TRACKS GENERALLY WESTWARD ALONG THE PERIPHERY OF THE STR. AS FAVORABLE CONDITIONS PERSIST, THE SYSTEM SHOULD INTENSIFY TO 60 KTS PRIOR TO MAKING LANDFALL OVER THE EASTERN PHILIPPINES NEAR TAU 18. AS IT TRANSITS OVER THE ARCHIPELAGO, THE SYSTEM SHOULD MAINTAIN INTENSITY (OR POSSIBLY WEAKEN SLIGHTLY) BEFORE THE SYSTEM RE-EMERGES OVER THE SOUTH CHINA SEA WHERE IT IS EXPECTED TO RE-INTENSIFY TO A PEAK OF 80 KNOTS BY TAU 72. NUMERICAL GUIDANCE IS IN GOOD AGREEMENT THROUGH TAU 72 WITH A 90NM SPREAD IN SOLUTIONS AT TAU 72. CONSEQUENTLY, THERE IS NOW HIGH CONFIDENCE IN THIS PHASE OF THE FORECAST. C. AFTER TAU 72, NUMERICAL GUIDANCE DIVERGES AS THE SYSTEM APPROACHES CENTRAL VIETNAM WITH A 135NM SPREAD IN SOLUTIONS NEAR THE LANDFALL POINT. TS 21W WILL WEAKEN AS IT APPROACHES THE COAST AND BEGINS INTERACTING WITH LAND, AND WILL WEAKEN SIGNIFICANTLY AS IT TRACKS INLAND, HOWEVER, THE SYSTEM IS EXPECTED TO PRODUCE HEAVY RAINFALL. DUE TO THE MODEL SPREAD IN THE LATER TAUS, THERE IS OVERALL FAIR CONFIDENCE IN THE JTWC FORECAST TRACK.// NNNN