MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 04W (FOUR) WARNING NR 01// RMKS// 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TROPICAL DEPRESSION (TD) 04W (FOUR), LOCATED APPROXIMATELY 254 NM WEST-NORTHWEST OF MANILA, PHILIPPINES, HAS TRACKED NORTHWESTWARD AT 08 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) SHOWS THE SYSTEM HAS STEADILY CONSOLIDATED AS CONVECTIVE TOPS IN THE CENTRAL DENSE OVERCAST DEEPENED AND FORMATIVE BANDS BEGAN TO CONSOLIDATE. THE INITIAL POSITION IS BASED ON THE MSI AND DOPPLER RADAR LOOP FROM PAGASA WITH FAIR CONFIDENCE. THE CENTER ALSO LINES UP WELL WITH A LOW REFLECTIVITY CIRCULATION FEATURE IN THE 102305Z SSMIS MICROWAVE PASS. THE INITIAL INTENSITY OF 25 KNOTS IS BASED ON AN OVERALL ASSESSMENT OF DVORAK ESTIMATES FROM PGTW, KNES, AND RJTD RANGING FROM T1.0 TO T1.5. UPPER LEVEL ANALYSIS INDICATES TD 04W IS IN AN AREA OF LOW VERTICAL WIND SHEAR (VWS) AND STRONG EQUATORWARD OUTFLOW. THE CYCLONE IS TRACKING ALONG THE SOUTHWESTERN PERIPHERY OF THE LOW REFLECTION OF THE SUBTROPICAL RIDGE (STR). 3. FORECAST REASONING. A. THIS IS THE INITIAL FORECAST AND SETS THE FORECAST PHILOSOPHY FOR THIS SYSTEM. B. TD 04W IS EXPECTED TO CONTINUE ON ITS TRACK AND MAKE LANDFALL JUST EAST OF HONG KONG SHORTLY AFTER TAU 36, ROUND THE WESTERN EDGE OF THE STR, EXIT INTO THE YELLOW SEA AND ACCELERATE EAST-NORTHEASTWARD. THE FAVORABLE UPPER LEVEL DYNAMICS, IN ADDITION TO THE WARM WATERS OF THE SOUTH CHINA SEA, WILL FUEL GRADUAL INTENSIFICATION PEAKING AT 50 KNOTS BEFORE LANDFALL. AFTERWARD, LAND INTERACTION AND INCREASING VWS WILL RAPIDLY ERODE THE SYSTEM. C. AFTER TAU 72, TD 04W WILL CONTINUE TO DETERIORATE THEN DISSIPATE OVER WATER JUST NORTHEAST OF OKINAWA. DYNAMIC MODEL GUIDANCE IS IN GOOD AGREEMENT WITH HWRF AS THE NOTABLE OUTLIER TO THE RIGHT OF THE MODEL ENVELOPE. THE JTWC TRACK IS LAID JUST TO THE LEFT OF CONSENSUS TO OFFSET HWRFS UNLIKELY TIGHT TURN AROUND THE STR. IN VIEW OF THE FORMATIVE NATURE OF THE SYSTEM, THERE IS LOW CONFIDENCE TO THE INITIAL JTWC FORECAST TRACK.// NNNN NNNN