WDPN31 PGTW 011500 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 22W (TWENTYTWO) WARNING NR 03// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. TROPICAL STORM (TS) 22W (TWENTYTWO), LOCATED APPROXIMATELY 105 NM EAST-NORTHEAST OF MANILA, PHILIPPINES, HAS TRACKED NORTHWESTWARD AT 15 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY (EIR) SHOWS FORMATIVE BANDS HAVE BECOME MORE SOLID AND HAVE WRAPPED TIGHTER INTO THE LOW LEVEL CIRCULATION CENTER. A 010945Z SSMIS MICROWAVE PASS HIGHLIGHTS A DEEP CONTINUOUS BAND ARCING FROM THE NORTHWEST TO THE SOUTHEAST. THE INITIAL POSITION IS BASED ON A RADAR COMPOSITE REFLECTIVITY LOOP FROM THE PHILIPPINES DOST WITH HIGH CONFIDENCE. THE INITIAL INTENSITY OF 35 KNOTS IS BASED ON OBJECTIVE DVORAK ESTIMATES, IS CONSISTENT WITH THE MICROWAVE SIGNATURE, AND REFLECTS THE IMPROVED CONDITION OF THE SYSTEM. UPPER-LEVEL ANALYSIS INDICATES TS 22W IS IN A FAVORABLE AREA WITH GOOD RADIAL OUTFLOW AND LOW (05-10 KNOT) VERTICAL WIND SHEAR. THE CYCLONE IS TRACKING ALONG THE SOUTHERN PERIPHERY OF THE SUBTROPICAL RIDGE (STR) TO THE NORTH. 3. FORECAST REASONING. A. THERE IS NO SIGNIFICANT CHANGE IN THE FORECAST PHILOSOPHY FROM THE PREVIOUS PROGNOSTIC REASONING BULLETIN. B. UNDER THE STEERING INFLUENCE OF THE STR, TS 22W WILL CONTINUE TO TRACK WEST-NORTHWESTWARD THROUGHOUT THE FORECAST PERIOD. FAVORABLE UPPER LEVEL CONDITIONS, IN ADDITION TO WARM SEA SURFACE TEMPERATURES (SSTS) IN THE PHILIPPINE SEA, WILL FURTHER STRENGTHEN THE TS OVER THE NEXT SIX HOURS PRIOR TO LANDFALL NEAR BALER, QUEZON PROVINCE. AFTER LANDFALL, HOWEVER, INTERACTION WITH THE MOUNTAIN RANGES OF LUZON WILL WEAKEN IT BACK TO A TD BEFORE IT RE-EMERGES BACK ON THE WARM WATERS OF THE SOUTH CHINA SEA JUST NORTH OF MANILA BAY. CONTINUED FAVORABLE UPPER LEVEL CONDITIONS IN ADDITION TO THE WARM SSTS WILL PROMOTE FURTHER INTENSIFICATION, PEAKING TO 70 KNOTS BY TAU 66 BEFORE MAKING A SECONDARY LANDFALL OVER THE LEIZHOU PENINSULA. C. IN THE EXTENDED FORECAST PERIOD, TS 22W WILL DRAG ACROSS THE LEIZHOU PENINSULA AND BRIEFLY CROSS THE NORTHEASTERN PORTION OF THE GULF OF TONKIN BEFORE MAKING A FINAL LANDFALL JUST NORTH OF THE VIETNAM-CHINA BORDER. LAND INTERACTION WILL RAPIDLY ERODE THE CYCLONE, REDUCING IT TO A WEAK TD BY TAU 120. DYNAMIC MODEL GUIDANCE IS IN FAIRLY TIGHT AGREEMENT, LENDING HIGH CONFIDENCE IN THE JTWC FORECAST TRACK.// NNNN