WDPN31 PGTW 061500 MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC// SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 10W WARNING NR 11// RMKS/ 1. FOR METEOROLOGISTS. 2. 12 HOUR SUMMARY AND ANALYSIS. A. RECENT RADAR AND INFRARED SATELLITE POSITION ESTIMATES INDIC- ATE THAT TS 10W (KAMMURI) HAS MADE LANDFALL ALONG THE SOUTH COAST OF CHINA APPROXIMATELY 140 NM WEST OF HONG KONG. RECENT INFRARED SATELLITE IMAGERY SHOWS THAT INCREASING LAND INTERACTION HAS INITIATED A BREAK DOWN IN THE CONVECTIVE STRUCTURE. B. THE CURRENT POSITION IS SITUATED SLIGHTLY EAST OF RECENT SATELLITE FIXES FROM PGTW AND RJTD AND IS WEIGHTED TOWARD A 061200Z RADAR FIX FROM HONG KONG. THE INTENSITY ESTIMATE OF 45 KNOTS IS CONSISTENT WITH DVORAK T-NUMBERS OF 2.5 FROM PGTW AND 3.0 FROM RJTD AND SYNOPTIC OBSERVATIONS NEAR THE STORM CENTER. THE TROPICAL STORM IS NOW TRACKING GENERALLY WESTWARD ALONG THE SOUTHERN PERIPHERY OF SUBTROPICAL RIDGING TO THE NORTH. 3. FORECAST REASONING A. THE FORECAST PHILOSOPHY HAS NOT CHANGED SIGNIFICANTLY SINCE THE PREVIOUS ISSUE OF THE PROGNOSTIC REASONING MESSAGE. B. SUBTROPICAL RIDGING ON THE POLEWARD SIDE OF TS 10W WILL CONTINUE TO STEER THE STORM WESTWARD OVER LAND UNTIL DISSIPATION COMPLETES BY TAU 24. OBSERVATIONAL AND NUMERICAL MODEL GUIDANCE SUGGESTS THAT A PORTION OF THE LOW LEVEL CIRCULATION MAY REMAIN OVER WATER AS THE DISSIPATING SYSTEM TRACKS WESTWARD. THIS INTER- ACTION WILL LIKELY FUEL CONVECTIVE DEVELOPMENT NEAR THE COAST BUT SHOULD NOT PRECLUDE DISSIPATION OF THE OVERALL CIRCULATION. FORECAST TEAM: ALPHA// NNNN