A heavy rain warning has been issued for the five border islands in the Yellow Sea and a heavy rain watch for the Seoul metro area, Gangwon Province and parts of the Jeolla and Gyeongsang provinces. 

With heavy rain set to pound most parts of the nation through Sunday, the interior and safety ministry on Friday activated a Level One emergency posture and raised the nation's warning level for heavy rainfall by a notch on its four-tier scale, from the lowest "attention," to "caution."

The Korea Forest Service issued “attention” on its warning level for landslides for all parts of the nation, excluding Jeju Island. 

The Korea Meteorological Administration forecast that through Sunday, more than 300 millimeters of rain will pound the eastern coasts and mountainous regions of Gangwon Province and more than 250 millimeters of rain will fall in Jeju’s mountainous areas. 

Busan and the coastal areas of South Gyeongsang Province are set to experience more than 200 millimeters of rain while the Seoul metro area and the Chungcheong Provinces are expected to see more than 150 millimeters of precipitation.