[Tomorrow's Weather] Heavy Rain Mainly in Jungbu Region... Nambu Region in Lull

Over 200mm of Rainfall Expected in the Seoul Metropolitan and Chungcheong Regions

During the night from the 17th to the 18th, heavy rain with hourly precipitation exceeding 70mm is expected to pour over the metropolitan area and the inland and mountainous regions of Gangwon, starting from the early morning of the 18th in Chungcheong.

Heavy rain is anticipated in various areas until the 19th, so preparations are necessary. The metropolitan area and Chungcheong region are expected to receive more than 200mm of additional rainfall. After the rain cloud band that brought heavy rain to northern Gyeonggi in the early morning of the 17th moved away, all heavy rain warnings were lifted. However, starting at 4:10 PM, heavy rain warnings have been gradually reissued beginning with Incheon and Gyeonggi’s Dongducheon, Yeoncheon, Pocheon, and Yangju. At 4:30 PM, heavy rain advisories were reissued for Incheon’s Ganghwa County and Gyeonggi’s Dongducheon, Yeoncheon, Pocheon, and Yangju.

At 4:45 PM, the heavy rain advisory for Incheon was upgraded to a heavy rain warning, and a heavy rain warning was also issued for Gimpo City in Gyeonggi. At 4:50 PM, a heavy rain advisory was additionally issued for Cheorwon County in Gangwon. Heavy rain preliminary warnings remain in effect for the rest of the metropolitan area, Gangwon Yeongseo, northern and western Chungnam, and northern Chungbuk.

On the 17th, when Hongjecheon in Seodaemun-gu, Seoul, was closed due to heavy rain in Seoul and northern Gyeonggi Province, a citizen looked at the swollen water. The Korea Meteorological Administration issued a heavy rain advisory for Seoul. Photo by Jo Yongjun jun21@

Most regions nationwide are expected to experience continued monsoon rain on the 18th. Rain will pour mainly over the central regions on the 18th, while the southern regions will mostly see a lull. In Jeju, rain is expected to fall intermittently until the morning.

In the metropolitan area, hourly rainfall of 30 to 60mm, and at times exceeding 70mm, is expected until the morning of the 18th. Similar intense heavy rain will fall in the inland and mountainous areas of Gangwon and Chungcheong from the night of the 17th through the morning of the 18th and again from the early morning to the afternoon of the 18th, comparable to the metropolitan area.

In Jeonbuk, hourly rainfall around 30mm is expected from early morning to morning on the 18th, and in Gwangju and northern Jeonnam, 20 to 30mm per hour is expected during the same period. In the inland areas of Gyeongbuk, 20 to 30mm per hour of rain is forecast from morning to afternoon on the 18th.

Heavy rain will continue in various places between the 18th and 19th. From late afternoon on the 18th to early morning on the 19th, hourly rainfall of 30 to 60mm is expected in Seoul and southern Gyeonggi, and around 30mm per hour in northern Gyeonggi during the same period. In the inland and mountainous areas of Gangwon and Chungcheong, 30 to 60mm per hour of rain will fall from night on the 18th to early morning on the 19th, with some places in Gangwon’s inland and mountainous areas experiencing hourly precipitation exceeding 70mm.

In Gwangju, Jeonnam (excluding the southern coast), Jeonbuk, Daegu, and Gyeongbuk, rain is expected between early morning and morning on the 19th, with hourly rainfall of 30 to 50mm and around 30mm respectively. On the 19th, precipitation will concentrate in Chungcheong and the southern regions, while the metropolitan area and Gangwon inland and mountainous areas will experience a lull with occasional rain.

The expected additional rainfall until the 19th is 80 to 150mm in Chungcheong (with Daejeon, Sejong, Chungnam, and northern Chungbuk possibly exceeding 200mm), 50 to 150mm in the metropolitan area and the five western islands (with the metropolitan area possibly exceeding 200mm), 50 to 100mm in Gangwon inland and mountainous areas (with central and southern inland and mountainous areas possibly exceeding 180mm, and northern inland and mountainous areas possibly exceeding 150mm), and 20 to 60mm along the Gangwon east coast.

In Honam (excluding the southern coast of Jeonnam) and northern Gyeongbuk, 30 to 100mm of rain is expected (with Jeonbuk and northern Gyeongbuk possibly exceeding 150mm), 30 to 80mm in Daegu and southern Gyeongbuk, 20 to 60mm in Gangwon east coast, southern coast of Jeonnam, Busan, Ulsan, Gyeongnam, Ulleungdo, and Dokdo, and 5 to 40mm in Jeju.

Since the start of the monsoon in Jeju on the 19th of last month until the 16th of this month, the nationwide average accumulated precipitation was 342.5mm, far exceeding the average for the same period (243.5mm) from 1990 to 2020, ranking as the 7th highest in 52 years since 1973.