South Korea's central region, including the greater Seoul area, was choked by yellow dust blowing in from the inland deserts in northern China for the second consecutive day on Wednesday, a state forecasting agency said.

According to the National Institute of Environmental Research's Air Quality Forecasting Center, the density of fine dust particles smaller than 10 micrometers in diameter, known as PM 10, remained at the "bad" level in Seoul and surrounding areas, the central provinces of Chungcheong, and the southeastern province of North Gyeongsang and neighboring Daegu.

The weather authorities here categorize concentrations of PM 10 between zero and 30 micrograms as "good," between 31 and 80 as "normal," between 81 and 150 as "bad" and more than 151 as "very bad."

The PM 10 figures are expected to reach the bad level in all of South Korea in the afternoon, the center said.

It forecast that Seoul, the southern parts of Gyeonggi Province that surrounds the capital, and South Chungcheong Province will continue to be affected by bad levels of fine dust on Thursday.

As of 1 p.m., the daily average concentration of PM 10 reached 104 micrograms per cubic meter in Gyeonggi Province, 99 micrograms in Seoul, 97 micrograms in South Chungcheong, 95 micrograms in the central administrative city of Sejong, 93 micrograms in Incheon, 92 micrograms in Daejeon and 90 micrograms in Daegu, the center noted. (Yonhap)