MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 02W (SANBA) WARNING NR 15// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TROPICAL STORM 02W (SANBA), LOCATED APPROXIMATELY 806 NM EAST OF PUERTO PRINCESA, PALAWAN, PHILIPPINES, HAS TRACKED WESTWARD AT 15 KNOTS OVER THE PAST SIX HOURS. ANIMATED MSI SHOWS THE SYSTEM HAS UNDERGONE ANOTHER CYCLIC CONVECTIVE FLARE WITH NO DISCERNIBLE IMPROVEMENT IN ORGANIZATION OR DEGREE OF WRAP INTO A DEFINED LLC. THE INITIAL POSITION IS BASED ON THE LLC FEATURE IN THE MSI WITH FAIR CONFIDENCE. THE INITIAL INTENSITY OF 35 KNOTS IS BASED ON THE HIGHER END OF AGENCY DVORAK ESTIMATES RANGING FROM T2.0 TO T2.5. UPPER LEVEL ANALYSIS INDICATES THE SYSTEM IS IN AN AREA OF MODERATE (15-20 KNOT) VWS; HOWEVER, A STRONG POLEWARD OUTFLOW IN ADDITION TO WARM (29C) SSTS, IS PROVIDING AMPLE VENTILATION TO THE ASSOCIATED CONVECTION. TS 02W IS TRACKING ALONG THE SOUTHERN PERIPHERY OF THE STR TO THE NORTH. 3. FORECAST REASONING. A. THERE IS NO CHANGE IN THE FORECAST PHILOSOPHY SINCE THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. TS 02W WILL TRACK GENERALLY WEST-NORTHWESTWARD UNDER THE STR TOWARD THE SOUTHERN PHILIPPINES THROUGH TAU 12. THE AFOREMENTIONED MARGINALLY FAVORABLE ENVIRONMENTAL CONDITIONS WILL ALLOW FOR SLIGHT INTENSIFICATION TO 40 KNOTS. AFTERWARD, THE STR WILL SLIGHTLY BUILD AND DRIVE THE SYSTEM MORE WESTWARD AFTER MAKING LANDFALL OVER NORTHERN MINDANAO JUST PRIOR TO TAU 24. LAND INTERACTION WILL SLIGHTLY WEAKEN THE SYSTEM AND BY TAU 36, IT WILL BE REDUCED TO A 35-KNOT TS AS IT TRACKS ACROSS THE SULU SEA, PALAWAN, AND INTO THE SOUTH CHINA SEA (SCS). C. IN THE EXTENDED TAUS, TS SANBA WILL TRACK MORE NORTHWESTWARD IN THE SCS TOWARD SOUTHERN VIETNAM IN RESPONSE TO A RECEDING STR. MARGINAL CONDITIONS IN THE SCS ASSOCIATED WITH A COLD SURGE WILL CAUSE THE SYSTEM TO GRADUALLY WEAKEN TO 25 KNOTS BY TAU 120. DYNAMIC MODEL GUIDANCE IS IN STRONG AGREEMENT UP TO TAU 48, LENDING HIGH CONFIDENCE IN THE INITIAL TO MID PORTION OF THE JTWC FORECAST TRACK. AFTERWARD, THERE IS A SIGNIFICANT SPREAD AMONG THE CONSENSUS MEMBERS, LENDING LOW CONFIDENCE TO THE EXTENDED PORTION OF THE JTWC TRACK FORECAST.// NNNN NNNN