Seoul Under PM2.5 Disaster Warning as Unhealthy Smog Lingers Across Korea

Smog lingered over western parts of South Korea on Monday as air quality remained in the unhealthy range. The Seoul metropolitan area, South Chungcheong Province, and North Jeolla Province reported poor air quality, while Incheon and Gyeonggi Province were under ultrafine-dust advisories. A PM2.5 disaster warning was issued for the capital region and Chungnam, with emergency reduction measures in place.

Forecasters said rain would sweep across the country tomorrow, likely improving air quality in the southern regions. Central regions could still see lingering dust if rainfall proves insufficient.

Showers are forecast to begin in the pre-dawn hours around the morning commute, with most rain ending by the afternoon. Some southern coast regions and Jeju Island could see rain continuing into the night. Rainfall is expected to total 5–10 mm in Seoul and the central region and in North Gyeongsang, 10–30 mm along the southern coast, and up to 70 mm in Jeju’s mountainous areas. In the high elevations of Gangwon Province, snow could total up to 5 cm.

Temperatures are set to fall as a result of the precipitation, with daytime highs 5–7 degrees Celsius lower than today. Early mornings will be cooler: Seoul around 6°C, about 3°C warmer than today. The daytime high in Seoul and Daejeon is forecast at about 11°C. In Gwangju and Ulsan, morning temps around 7°C with daytime near 11°C in Andong and Jeonju.

Officials cautioned that the rain may not fully clear the dust, particularly in central regions where particles linger in the air.

This weather update is issued by the Korea Meteorological Administration and carried by Yonhap News Agency. The PM2.5 disaster warning is a public-health measure intended to curb emissions during periods of degraded air quality.

Why this matters for the United States: South Korea is a major hub for semiconductors and consumer electronics, and air-quality fluctuations and weather disruptions can affect industrial activity, worker health, and transportation logistics linked to global supply chains. U.S. companies with operations or investments in Korea, as well as travelers and students, may be affected by outdoor air-quality advisories and precipitation patterns. The episode also highlights broader environmental and regional air-pollution dynamics that intersect with U.S. policy discussions on climate, health, and international cooperation.