MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 13W (NOUL) WARNING NR 007// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TROPICAL STORM (TS) 13W (NOUL), LOCATED APPROXIMATELY 363 NM EAST-SOUTHEAST OF DA NANG, VIETNAM, HAS TRACKED WEST-NORTHWESTWARD AT 10 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY DEPICTS A PARTIALLY-EXPOSED, WELL-DEFINED LOW- LEVEL CIRCULATION CENTER (LLCC), WHICH SUPPORTS THE INITIAL POSITION WITH GOOD CONFIDENCE, WITH LIMITED DEEP CONVECTION OVER THE WESTERN QUADRANT. A 162228Z AMSU 89GHZ IMAGE REVEALS LIMITED DEEP CONVECTIVE BANDING OVER THE WESTERN SEMICIRCLE. THE INITIAL INTENSITY REMAINS ASSESSED AT 45 KNOTS BASED ON THE HIGHER END OF DVORAK ESTIMATES RANGING FROM T2.5 TO T3.0 (35 TO 45 KNOTS). ADT ESTIMATES ARE HIGHER AT 3.4-3.5 (ABOUT 55 KNOTS) WITH A 162227Z SATCON ESTIMATE OF 50 KNOTS. A 170047Z ASCAT-A IMAGE INDICATED 40-45 KNOT WINDS OVER THE WESTERN QUADRANT, WHICH ALSO SUPPORTS THE INITIAL INTENSITY ESTIMATE. ENVIRONMENTAL ANALYSIS INDICATES PERSISTENT NORTHEASTERLY VERTICAL WIND SHEAR (VWS) OF 20-25 KNOTS OFFSET BY VIGOROUS EQUATORWARD OUTFLOW, WARM SST VALUES (31C) AND HIGH OCEAN HEAT CONTENT VALUES. ANIMATED WATER VAPOR IMAGERY REVEALS WEAK POLEWARD OUTFLOW RESTRICTED BY CONVERGENT FLOW TO THE NORTH. 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 CONTINUE TO TRACK GENERALLY WEST-NORTHWESTWARD UNDER THE STEERING INFLUENCE OF THE STR THROUGHOUT THE FORECAST PERIOD. AS IT TRAVERSES OVER THE VERY WARM WATERS OF THE SOUTH CHINA SEA, IT WILL CONTINUE TO STEADILY INTENSIFY DESPITE CONTINUED MODERATE TO HIGH (15-25 KTS) VWS AS A RESULT OF THE WARM SSTS AND STRONG EQUATORWARD OUTFLOW AND REACH A MAXIMUM INTENSITY OF 60 KTS BY TAU 24. NEAR TAU 30 THE SYSTEM WILL MAKE LANDFALL NEAR HUE, VIETNAM. AFTER MAKING LANDFALL THE SYSTEM WILL BEGIN TO WEAKEN DUE TO INTERACTION WITH THE MOUNTAINOUS TERRAIN. AS TS NOUL TRACKS DEEPER INTO SOUTHEAST ASIA, IT WILL BEGIN TO DISSIPATE OVER LAND AND SHOULD DISSIPATE BY TAU 48. NUMERICAL MODEL SOLUTIONS ARE IN GOOD AGREEMENT WITH A 92 NM SPREAD IN SOLUTIONS AT TAU 24, LENDING OVERALL HIGH CONFIDENCE IN THE JTWC FORECAST TRACK.// NNNN NNNN