Heavy rain has been pouring since the beginning of the monsoon season. Overnight, some areas in the northwestern part of the metropolitan area received more than 100 mm of rain. Even in areas where it has not rained significantly yet, strong rain is forecasted for the 20th and 21st, so caution is needed.
According to the Korea Meteorological Administration on the 20th, 144 mm of rain fell in Seo-gu (Geumgok-dong), Incheon, from 9 p.m. the previous night to 10 a.m. that day. In Gimpo (Yangchon) and Pocheon (Idong), 155.5 mm and 109 mm of rain fell, respectively, while Hwacheon (Gwangdeok Pass) in Gangwon received 107.5 mm of rain.
The rain poured down very heavily overnight. In Seo-gu (Geumgok-dong), Incheon, 63.0 mm of rain fell during one hour from 3:58 a.m., and in Yangju (Baekseok-eup), 60.0 mm fell during one hour from 4:43 a.m. Once the rain exceeds 50 mm per hour, it becomes difficult to maintain visibility, even when operating the wipers at the fastest speed.
In Dongducheon, 50.8 mm of rain fell from 4:52 a.m. for one hour. This is the highest hourly rainfall recorded in June since weather observations began in Dongducheon in February 1998. Incheon also recorded 38.2 mm of rain during one hour from 3:38 a.m., marking the third-highest hourly rainfall record in June since modern weather observations began in August 1904.
The rain in Seoul is still relatively light. At the same time, the rainfall at the representative observation point in Jongno District (Seoul Weather Observation Station) is 24.4 mm. However, in some areas of Eunpyeong and Gangseo Districts in Seoul, it has been reported that over 40 mm of rain has fallen.
The monsoon rain is just starting. While rain will continue in the central region, Honam, and Jeju that day, it is expected to spread to Yeongnam between morning and daytime. Afterwards, rain will persist in the metropolitan area until the morning of the 21st and in the remaining central region until the afternoon, while the southern region and Jeju will see rain continue until night.
In particular, heavy rain is expected overnight into Saturday, the 20th. The forecasted rainfall for the 20th and 21st is as follows: ▲ Seoul, Incheon, northern Gyeonggi, central and northern inland Gangwon, southern Daejeon and Chungcheongnam-do, and northern Jeollabuk-do will receive more than 150 mm; ▲ Southern Gyeonggi, southern inland Gangwon, northern Sejong and Chungcheongnam-do, Chungcheongbuk-do, and northern Gwangju and Jeollanam-do will receive more than 120 mm; ▲ Chungcheong region and Jeollabuk-do can expect 50-100 mm; ▲ Gwangju Metropolitan City and Jeollanam-do, Daegu and Gyeongsangbuk-do, and western Gyeongsangnam-do can expect 30-80 mm; ▲ Jeju Island will see 20-80 mm; ▲ Busan, Ulsan, and Gyeongsangnam-do, Ulleungdo, and Dokdo will receive 20-60 mm; ▲ Eastern coast of Gangwon will see 10-50 mm.