On July 20, 2026, the nationwide air quality for ultrafine particulate matter is forecast to be at the "Good" level.
According to the Korea Environment Corporation’s forecast overview, all regions are expected to range from “Good” to “Moderate.”
Regarding the causes, "In some central-western and southeastern regions, concentrations are expected to rise in the morning as fine dust lingering from the previous day and domestically generated fine dust accumulate due to stagnant air and converging air currents; however, concentrations are expected to decrease in the afternoon due to favorable atmospheric dispersion and precipitation, resulting in a daily average concentration of 'Moderate,'" the agency analyzed.
Since PM2.5 concentrations will not be high across all regions, there should be no significant disruption to outdoor activities.
Moderate — Seoul, Ulsan, Busan (3 regions)
Good — Jeju, South Jeolla, North Jeolla, Gwangju, South Gyeongsang, North Gyeongsang, Daegu, South Chungcheong, North Chungcheong, Sejong, Daejeon, Yeongdong, Yeongseo, Southern Gyeonggi, Northern Gyeonggi, Incheon (16 regions)
※ This article was automatically generated by a robot reporter based on air quality forecast data from the Korea Environment Corporation. (Release date: July 20, 2026, 5:00 a.m.)
