MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TYPHOON 33W (TEMBIN) WARNING NR 15// RMKS// 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TYPHOON (TY) 33W (TEMBIN), LOCATED APPROXIMATELY 413 NM EAST- SOUTHEAST OF HO CHI MINH CITY, VIETNAM, HAS TRACKED WESTWARD AT 11 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY DEPICTS A CONSOLIDATING SYSTEM WITH TIGHTLY-CURVED BANDING WRAPPING INTO A WELL-DEFINED CENTER. A 240550Z ATMS 165GHZ IMAGE REVEALS IMPROVED CONVECTIVE BANDING WITH AN EYEWALL SURROUNDING A MICROWAVE EYE FEATURE, WHICH SUPPORTS THE INITIAL POSITION WITH GOOD CONFIDENCE. UPPER-LEVEL ANALYSIS INDICATES A FAVORABLE ENVIRONMENT CHARACTERIZED BY LOW VERTICAL WIND SHEAR AND NEAR-RADIAL OUTFLOW. THE INITIAL INTENSITY IS ASSESSED AT 80 KNOTS BASED ON DVORAK INTENSITY ESTIMATES RANGING FROM T4.5 (77 KNOTS) TO T5.0 (90 KNOTS). TY 33W IS TRACKING WESTWARD ALONG THE SOUTHERN PERIPHERY OF AN EAST- WEST ORIENTED SUBTROPICAL RIDGE ENTRENCHED TO THE NORTH. 3. FORECAST REASONING. A. THERE IS NO SIGNIFICANT CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. TY 33W WILL CONTINUE TO TRACK WESTWARD UNDER THE STEERING INFLUENCE OF THE AFOREMENTIONED STR THROUGH TAU 36. TY TEMBIN WILL MAINTAIN INTENSITY AT 80 KNOTS THROUGH TAU 12 DUE TO WARM SST AND FAVORABLE OUTFLOW. AFTER TAU 12, TY TEMBIN WILL WEAKEN STEADILY AS IT TRACKS OVER COOLER SST AND INTERACTS WITH THE SOUTHERN COAST OF VIETNAM. DESPITE RE-EMERGING OVER THE GULF OF THAILAND NEAR TAU 48, THE SYSTEM IS EXPECTED TO CONTINUE WEAKENING AS IT ENCOUNTERS INCREASING VERTICAL WIND SHEAR. TY 33W WILL BEGIN DISSIPATING AS IT MAKES LANDFALL OVER THE MALAY PENINSULA NEAR TAU 72. DYNAMIC MODEL GUIDANCE REMAINS IN GOOD AGREEMENT THROUGH TAU 72 WITH A 160NM SPREAD IN SOLUTIONS AT TAU 72. C. AFTER TAU 72, TY 33W IS EXPECTED TO TURN WEST-NORTHWESTWARD AS IT TRACKS ALONG THE SOUTHWESTERN PERIPHERY OF THE STR TOWARD A WEAKNESS ASSOCIATED WITH AN APPROACHING MID-LATITUDE SHORTWAVE TROUGH. TY 33W IS FORECAST TO DISSIPATE BY TAU 96 DUE TO INTERACTION WITH LAND AND INCREASING VERTICAL WIND SHEAR. OVERALL, DYNAMIC MODEL GUIDANCE REMAINS IN GOOD AGREEMENT, THEREFORE, THERE IS HIGH CONFIDENCE IN THE JTWC TRACK FORECAST.// NNNN NNNN