[Weather] Superfine dust in Seoul and other metropolitan areas "bad"...the atmospheric congestion overnight.

As the atmosphere stagnated overnight, the concentration of ultrafine dust in the metropolitan area, including Seoul, rose to the level of "bad."

The National Institute of Environmental Research said pollutants accumulated as the atmosphere stagnated overnight, and ultrafine dust concentrations in Seoul, Incheon and Gyeonggi Province reached a "bad" level from 36 to 39μg per cubic meter.

In addition, smog from China is expected to flow in while the atmosphere is stagnant tonight (20th), adding that the Midwest is likely to see "bad" levels of ultrafine dust tomorrow.

If the concentration of ultrafine dust exceeds 36μg per cubic meter, it is classified into a 'bad' stage.