Rainy season to reach Jeju on Friday, spreading north through mid-next week

A stationary front moving northward is expected to bring renewed monsoon rain to Jeju on Friday afternoon. The rain will gradually spread north — reaching South Jeolla Province in the early hours of Saturday, South Gyeongsang Province in the morning, North Jeolla Province in the afternoon, and southern Chungcheong and southern North Gyeongsang Province by night.

Forecast rainfall through Saturday includes 30–80 millimeters for Jeju and southern South Jeolla Province, with mountain areas potentially receiving more than 120 millimeters. Western and southern coastal areas of South Gyeongsang Province can expect 20–60 millimeters. Gwangju, northern South Jeolla Province, North Jeolla Province, Busan, Ulsan and most of South Gyeongsang Province are forecast to receive 5–40 millimeters. Daejeon, southern South Chungcheong Province, southern North Chungcheong Province, Daegu and southern North Gyeongsang Province are expected to see 5–10 millimeters.

On Sunday, rain will continue over the Chungcheong region, southern provinces and Jeju, with the precipitation zone expanding to southern Gyeonggi Province and central and southern Gangwon Province by nightfall. The monsoon rain is then forecast to cover the entire country on Monday, return to the Chungcheong region, southern provinces and Jeju on Tuesday and Wednesday, and reach central regions again on Thursday.

Meanwhile, atmospheric instability will bring showers to central regions and the inland and northeastern mountain areas of North Gyeongsang Province from Friday morning through the night. Expected shower totals are 5–40 millimeters for central regions — around 5 millimeters along Gangwon Province's East Sea coast — and 5–30 millimeters for northern inland and northeastern mountain areas of North Gyeongsang Province.

Temperatures will climb above 30 degrees Celsius inland as warm, humid air flows in from the south. The heat index, factoring in humidity, is expected to reach a high of around 31 C. Friday morning lows are forecast at 18–22 C, with afternoon highs of 25–31 C.