The Korea Meteorological Administration forecast heavy rain and strong winds for northern Gyeonggi Province and the Seoul metropolitan area on Tuesday [1].

This weather system poses a significant risk of flash flooding and wind damage across several provinces, threatening infrastructure in the capital region and beyond.

Precipitation is expected to begin around 12 p.m. today in the Seoul metropolitan area, Chungnam, and Honam [2]. Rain is forecast to reach the Yeongnam region by tonight [2]. The heaviest rainfall is expected to occur between 8 p.m. and midnight [1, 2].

Meteorologists warn that northern Gyeonggi Province could see maximum rainfall of 120 mm or more [1]. Some areas in that region may experience hourly rainfall rates of 50 mm per hour or more [1]. Other regions are also at risk; northern Gangwon Province is expected to receive 100 mm or more, while the wider Seoul metropolitan area may see between 30 mm and 100 mm [1].

Strong winds are accompanying the rain. The agency issued a pre-warning for wind gusts of 20 m/s or higher [1, 3].

The severe weather is being driven by tropical moisture from the remnants of Typhoon Bobi [1, 2]. This moisture is interacting with cold air and the Korean mountain ranges to produce the intense precipitation [1, 2].

"Today tonight, heavy rain will pour down, centered on the metropolitan area, including northern Gyeonggi, and northern Gangwon," an unnamed anchor said [1].

“Northern Gyeonggi Province could see maximum rainfall of 120 mm or more”

The interaction between Typhoon Bobi's remnants and local topography creates a high-risk scenario for urban flooding in the Seoul metropolitan area. With hourly rainfall potentially hitting 50 mm, drainage systems may be overwhelmed, necessitating immediate emergency preparedness in northern Gyeonggi and Gangwon provinces.