WTKO20 RKSL 161200 KMA TROPICAL CYCLONE ADVISORY NO. 6 NAME 1818 RUMBIA ANALYSIS POSITION 161200UTC 30.6N 123.5E MOVEMENT NW 9KT PRES/VMAX 994HPA 39KT FORECAST 24HR POSITION 171200UTC 31.6N 117.0E WITHIN 0NM PRES/VMAX 998HPA 29KT KOREA METEOROLOGICAL ADMINISTRATION.