MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 13W (PODUL) WARNING NR 12// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TROPICAL STORM (TS) 13W (PODUL), LOCATED APPROXIMATELY 134 NM NORTHEAST OF DA NANG, VIETNAM, HAS TRACKED WESTWARD AT 17 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY DEPICTS A BROAD LOW-LEVEL CIRCULATION CENTER (LLCC) WITH DEEP CONVECTION DISPLACED OVER THE SOUTHWEST QUADRANT. A 290554Z AMSR2 36GHZ MICROWAVE IMAGE INDICATES LIMITED SHALLOW CONVECTIVE BANDING WRAPPING FROM THE NORTH QUADRANT INTO THE SOUTH QUADRANT OF A DEFINED LLCC, WHICH SUPPORTS THE INITIAL POSITION WITH FAIR CONFIDENCE. SURFACE OBSERVATIONS FROM SANYA (59948), APPROXIMATELY 34NM NORTH-NORTHWEST OF THE CENTER, SHOW EASTERLY WINDS (10-MINUTE AVERAGE) AT 21 KNOTS AND SLP NEAR 993.8MB. A PARTIAL 29/0233Z ASCAT- C IMAGE SHOWS A SMALL PATCH OF 35 KNOT WINDS OVER THE EAST QUADRANT, WHICH, ALONG WITH DVORAK CURRENT INTENSITY ESTIMATES OF 2.5 (35 KNOTS), SUPPORTS THE INITIAL INTENSITY ASSESSMENT OF 35 KNOTS. UPPER- LEVEL ANALYSIS CONTINUES TO REVEAL A MARGINAL ENVIRONMENT WITH STRONG (25 TO 30 KNOTS) NORTHEASTERLY VERTICAL WIND SHEAR AND BROAD DIFFLUENCE. TS 13W IS TRACKING ALONG THE SOUTHERN PERIPHERY OF A SUBTROPICAL RIDGE (STR). 3. FORECAST REASONING. A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. TS PODUL WILL CONTINUE TO TRACK WESTWARD UNDER THE STEERING INFLUENCE OF THE STR AND SHOULD MAKE LANDFALL OVER EASTERN VIETNAM NEAR TAU 12. THE SYSTEM WILL RAPIDLY DISSIPATE AS IT TRACKS INLAND OVER MOUNTAINOUS TERRAIN. THE NUMERICAL MODELS ARE IN TIGHT AGREEMENT LENDING HIGH CONFIDENCE IN THE JTWC TRACK FORECAST WHICH IS POSITIONED CLOSE TO THE MULTI-MODEL CONSENSUS.// NNNN NNNN