MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 13W (NOUL) WARNING NR 010// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TROPICAL STORM (TS) 13W (NOUL), LOCATED APPROXIMATELY 105 NM EAST OF DA NANG, VIETNAM, HAS TRACKED WEST-NORTHWESTWARD AT 13 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY DEPICTS A SLIGHT IMPROVEMENT IN CONVECTIVE BANDING OVER THE WESTERN SEMICIRCLE WITH DEEP CONVECTION OBSCURING THE LOW-LEVEL CIRCULATION CENTER (LLCC). A 171811Z ATMS 88.2GHZ MICROWAVE IMAGE INDICATES CONVECTIVE BANDING OVER THE SOUTHERN SEMICIRCLE WITH SHALLOW BANDING OVER THE NORTHERN SEMICIRCLE WRAPPING TIGHTLY INTO A DEFINED LLCC, WHICH SUPPORTS THE INITIAL POSITION WITH GOOD CONFIDENCE. SURFACE WINDS ALONG THE PERIPHERY OF THE SYSTEM HAVE INCREASED WITH HUE (VVPB) SHOWING 23 KNOTS GUSTING TO 36 KNOTS WITH SLP NEAR 994MB AND SANYA (59948) OVER SOUTHERN HAINAN ISLAND AT 30 KNOTS. BASED ON THE SLIGHT IMPROVEMENT IN ORGANIZATION, THE INITIAL INTENSITY IS INCREASED TO 50 KNOTS BASED ON KNES/PGTW DVORAK CURRENT INTENSITY ESTIMATES OF 3.0-3.5 (45-55 KNOTS) AND ADT ESTIMATES RANGING FROM 3.0-3.2 (45-50 KNOTS). ENVIRONMENTAL ANALYSIS INDICATES PERSISTENT NORTHEASTERLY VERTICAL WIND SHEAR (VWS) OF 25-30 KNOTS OFFSET BY VIGOROUS EQUATORWARD OUTFLOW AND WARM SST VALUES (31C). ADDITIONALLY, ANIMATED WATER VAPOR IMAGERY REVEALS IMPROVING POLEWARD OUTFLOW. TS NOUL CONTINUES TO TRACK ALONG THE SOUTHERN PERIPHERY OF THE SUBTROPICAL RIDGE (STR) POSITIONED TO THE NORTH. 3. FORECAST REASONING. A. THERE IS NO SIGNIFICANT CHANGE TO THE FORECAST PHILOSOPHY FROM THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. TS NOUL WILL TRACK GENERALLY WEST-NORTHWESTWARD TO WESTWARD THROUGH THE FORECAST PERIOD UNDER THE STEERING INFLUENCE OF THE STR ENTRENCHED TO THE NORTH. THE SYSTEM IS FORECAST TO INTENSIFY SLIGHTLY TO 55 KNOTS PRIOR TO MAKING LANDFALL NEAR TAU 12, AND WILL DISSIPATE AS IT TRACKS FURTHER INLAND OVER MOUNTAINOUS TERRAIN. NUMERICAL MODEL GUIDANCE REMAINS IN GOOD AGREEMENT WITH A 55 NM SPREAD IN SOLUTIONS AT TAU 12, LENDING HIGH CONFIDENCE IN THE JTWC FORECAST TRACK.// NNNN NNNN