WDPN31 PGTW 280300 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 35W (THIRTYFIVE) WARNING NR 15// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TROPICAL DEPRESSION (TD) 35W (THIRTYFIVE), LOCATED APPROXIMATELY 472 NM EAST-SOUTHEAST OF MANILA, PHILIPPINES, HAS TRACKED WESTWARD AT 06 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY DEPICTS A RAPIDLY-EXPANDING CENTRAL COLD COVER (CCC) FEATURE, WHICH IS OBSCURING THE LOW-LEVEL CIRCULATION CENTER (LLCC). FORTUNATELY, ANIMATED MULTISPECTRAL SATELLITE IMAGERY REVEALS LOW-LEVEL CLOUD LINES WRAPPING INTO AN ELONGATED, PARTIALLY- EXPOSED LLCC LOCATED UNDER THE EASTERN EDGE OF THE CCC FEATURE. HOWEVER, CONFIDENCE IN THE INITIAL POSITION REMAINS POOR DUE TO THE POORLY-ORGANIZED CONVECTIVE STRUCTURE, QUASI-STATIONARY MOTION AND LACK OF RECENT HIGH-RESOLUTION MICROWAVE IMAGERY. A 280034Z ASCAT IMAGE ALSO DEPICTS A BROAD CENTER WITH 30 KNOT WINDS OVER THE SOUTHWEST QUADRANT (WITH POSSIBLY ISOLATED HIGHER VALUES UNDER THE DEEP CONVECTION OVER THE WEST QUADRANT). THE INITIAL INTENSITY REMAINS DIFFICULT TO ASSESS ESPECIALLY WITH THE CYCLING DEEP CONVECTIVE BURSTS OVER THE SYSTEM, HOWEVER, THE INITIAL INTENSITY HAS BEEN INCREASED SLIGHTLY TO 30 KNOTS BASED ON A RJTD DVORAK INTENSITY ESTIMATE OF T2.0 (30 KNOTS) AND THE ASCAT DATA. UPPER- LEVEL ANALYSIS SHOWS A MARGINALLY-FAVORABLE ENVIRONMENT WITH MODERATE EASTERLY VERTICAL WIND SHEAR (VWS) OFFSET BY STRONG DIFFLUENCE ALOFT. TD 35W IS TRACKING WESTWARD UNDER THE STEERING INFLUENCE OF A LOW- TO MID-LEVEL SUBTROPICAL RIDGE (STR) POSITIONED TO THE NORTH. 3. FORECAST REASONING. A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS PROGNOSTIC REASONING MESSAGE. B. THROUGH TAU 72, TD 35W WILL TRACK WESTWARD TO WEST- SOUTHWESTWARD ALONG THE SOUTHERN PERIPHERY OF THE AFOREMENTIONED STR. TD 35W IS EXPECTED TO INTENSIFY SLOWLY DUE TO PERSISTENT MODERATE VWS AND INTERACTION WITH LAND. THE BULK OF THE NUMERICAL MODEL GUIDANCE (INCLUDING EEMI, JGSI, AVNI AND AEMI) SUPPORTS THE JTWC FORECAST TRACK, HOWEVER, EGRI AND ECMI NOW SUGGEST DISSIPATION BY TAU 48 AS THE SYSTEM CROSSES THE CENTRAL PHILIPPINES. ANALYSIS OF ECMWF SLP FIELDS ACTUALLY SHOWS A BROAD, WEAK LOW PRESSURE AREA EMERGING OVER THE SULU SEA BY TAU 48 WITH A GRADUALLY RE- STRENGTHENING SYSTEM TRACKING INLINE WITH THE BULK OF THE GUIDANCE, FURTHER BOLSTERING THE JTWC FORECAST TRACK. NVGI AND AFUI REMAIN ON THE NORTHERN EDGE OF THE AIDS ENVELOPE WITH A MORE NORTHWESTWARD (UNLIKELY) TRACK IN THE EARLY TAUS. DUE TO THE 200NM SPREAD IN SOLUTIONS AT TAU 72 AND THE POTENTIAL FOR DISSIPATION PLUS POSSIBLE INTERACTION WITH A WEAK CIRCULATION (INVEST 97W) IN THE SOUTH CHINA SEA, THERE IS LOW CONFIDENCE IN THIS PHASE OF THE FORECAST TRACK. C. AFTER TAU 72, TD 35W WILL TURN WEST-SOUTHWESTWARD TO SOUTHWESTWARD IN RESPONSE TO A NORTHEAST SURGE EVENT. SLIGHT INTENSIFICATION IS EXPECTED TO A PEAK OF 45 KNOTS BY TAU 120. NUMERICAL MODEL GUIDANCE REMAINS IN POOR AGREEMENT, THEREFORE, THERE IS LOW OVERALL CONFIDENCE (HIGH UNCERTAINTY) IN THE JTWC FORECAST TRACK.// NNNN