WTKO20 RKSL 151800 KMA TROPICAL CYCLONE ADVISORY NO. 9 NAME 1607 CHANTHU ANALYSIS POSITION 151800UTC 30.2N 142.8E MOVEMENT NW 15KT PRES/VMAX 990HPA 47KT FORECAST 12HR POSITION 160600UTC 32.2N 141.6E WITHIN 30NM PRES/VMAX 990HPA 47KT 24HR POSITION 161800UTC 35.1N 141.0E WITHIN 75NM PRES/VMAX 992HPA 45KT 36HR POSITION 170600UTC 38.9N 141.9E WITHIN 100NM PRES/VMAX 994HPA 41KT 48HR POSITION 171800UTC 45.7N 144.1E WITHIN 0NM PRES 994HPA KOREA METEOROLOGICAL ADMINISTRATION.