WTKO20 RKSL 311800 KMA TROPICAL CYCLONE ADVISORY NO. 6 NAME 1604 NIDA ANALYSIS POSITION 311800UTC 19.6N 120.0E MOVEMENT NW 15KT PRES/VMAX 980HPA 56KT FORECAST 24HR POSITION 011800UTC 21.7N 115.0E WITHIN 75NM PRES/VMAX 960HPA 76KT 48HR POSITION 021800UTC 23.4N 109.8E WITHIN 125NM PRES/VMAX 980HPA 56KT 72HR POSITION 031800UTC 24.4N 105.5E WITHIN 0NM PRES 1002HPA KOREA METEOROLOGICAL ADMINISTRATION.