MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 04W (MAYSAK) WARNING NR 36// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TROPICAL STORM (TS) 04W (MAYSAK), LOCATED APPROXIMATELY 151 NM EAST-NORTHEAST OF MANILA, PHILIPPINES, HAS TRACKED WEST-NORTHWESTWARD AT 06 KNOTS KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED IR (EIR) IMAGERY SHOWS THE ASSOCIATED CONVECTION HAS SIGNIFICANTLY REDUCED AND WEAKENED AS IT APPROACHED LUZON. THE INITIAL POSITION IS EXTRAPOLATED FROM THE 041744Z NPP 165BT MICROWAVE PASS WITH FAIR CONFIDENCE. THE INITIAL INTENSITY OF 55 KNOTS IS BASED ON AN OVERALL ASSESSMENT OF DVORAK ESTIMATES FROM PGTW, KNES, AND RJTD. UPPER-LEVEL ANALYSIS INDICATES THE SYSTEM IS LOCATED IN AN AREA OF MODERATE (15 TO 20 KNOT) VERTICAL WIND SHEAR (VWS) PARTIALLY OFFSET BY RADIAL OUTFLOW. THE CYCLONE IS TRACKING ALONG THE SOUTHEASTERN PERIPHERY OF THE DEEP LAYERED SUBTROPICAL RIDGE (STR). 3. FORECAST REASONING. A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. TS MAYSAK WILL CONTINUE TRACKING NORTHWESTWARD THROUGH TAU 48 UNDER THE STEERING INFLUENCE OF THE STR, MAKING LANDFALL OVER SOUTHERN ISABELA IN THE NEXT FEW HOURS. INCREASING VWS AND LAND INTERACTION WILL GRADUALLY ERODE THE SYSTEM. HOWEVER, TS 04W WILL EMERGE IN THE SOUTH CHINA SEA AS A WEAK TROPICAL STORM. NEAR TAU 48, A NORTHEASTERLY COLD SURGE EVENT THROUGH THE STRAIGHTS OF TAIWAN WILL AID IN THE CONTINUED DISSIPATION OF TS MAYSAK. EXPECT COMPLETE DISSIPATION OF THE STORM BY TAU 72 AS IT DIPS SOUTHWESTWARD WITH THE LOW LEVEL FLOW. NUMERICAL MODEL GUIDANCE REMAINS IN GOOD AGREEMENT, LEADING TO HIGH CONFIDENCE IN THE JTWC FORECAST.// NNNN NNNN