Typhoon Nanmadol is likely to bring heavy rains and strong winds to the southern and eastern coastal areas from Sunday night.
According to the Korea Meteorological Administration on Sunday, the season's 14th typhoon passed the waters about 200 kilometers south-southeast of Japan's southwestern island Kagoshima at 9 a.m. Sunday.
Nanmadol, currently a "very strong" typhoon, is forecast to make landfall in Japan's Kyushu Island early on Monday and then move up northwestward.
The typhoon is expected to come closest to the Korean Peninsula between early Monday morning and afternoon, bringing up to 60 millimeters of heavy downpour per hour to the southeastern coastal areas.
Up to or more than 150 millimeters of rainfall is forecast for the southern coastal areas in Gyeongsang Province until Monday, with 50 to 100 millimeters for the eastern parts of Gangwon Province.
The weather agency also forecast strong winds of up to 35 meters per second for Jeju Island and the southeastern coastal areas between Sunday night and Monday morning.