South Korea Sees Dust-Laden Rain as Cross-Border Pollution Lingers

Most of Korea is forecast to be hit by rain that contains fine dust later this week, as high levels of particulate matter blown from China linger over the Korean Peninsula. The air quality advisory has already been activated in parts of the country due to the ongoing cross-border haze.

According to the Korea Meteorological Administration, the rain is expected to begin late at night and move into the early morning hours. In Chungcheong, Jeolla, western Gyeongsang, and Jeju, showers are projected to start between midnight and 6 a.m., then spread to most other regions by daytime. Some parts of the northeastern mountainous areas in Gangwon Province could see snow instead of rain.

Rainfall amounts vary by region. The capital area (Seoul, Incheon, and Gyeonggi Province) and the central inland regions of Gangwon and Chungcheong are expected to receive about 5–10 mm. Gwangju and the northern parts of Jeolla and Jeonbuk regions could see 5–20 mm. The southern Jeolla region, along with Busan and the southern coast of Gyeongsang, are forecast to receive 10–30 mm. Ulsan and inland areas of Gyeongsang may see 5–20 mm, and Daegu and northern Gyeongsang about 5–10 mm. Jeju Island could experience 10–50 mm, with mountainous areas possibly exceeding 70 mm.

The rain is likely to carry dust particles, as wildfire smoke from Liaoning Province in northeastern China has been drawn into the region by a northwesterly wind. Even as rain arrives, air quality in several areas is expected to deteriorate, reflecting the lingering cross-border pollution.

In the Seoul metropolitan area, northern Gangwon, and South Chungcheong, the fine dust concentration is forecast to be in the “unhealthy” range. Some areas, including Sejong, Chungbuk, Gwangju, Jeonbuk, Daegu, and Daegu/Gyeongbuk, are expected to remain in the unhealthy category only through the morning hours.

Outside the capital and nearby regions, air quality is expected to improve as rain disperses pollutants and washes the atmosphere. By the 19th, officials anticipate a return to more typical air conditions nationwide as winds shift and drier conditions resume.

Separately, temperatures are expected to remain above the seasonal average for this time of year. Overnight lows are forecast to be between 1 and 10 degrees Celsius, with daytime highs from 9 to 14 degrees Celsius on Thursday.

Why this matters to U.S. readers: Korea’s experience underscores how cross-border pollution from industrial activity and regional wildfires can affect daily life, health advisories, and productivity in major economies with global supply chains. For U.S. companies, the episode highlights why environmental conditions in East Asia matter for labor availability, transportation planning, and electronics and auto manufacturing ecosystems that rely on stable operating conditions in Korea. It also illustrates the importance of international cooperation and shared monitoring data in managing transboundary air pollution and its broader economic and health impacts.