Sections of five Beijing and eight Tianjin expressways are currently closed after thick fog smothered north China beginning Sunday night.

Sections of five Beijing and eight Tianjin expressways are closed after thick fog smothered north China beginning at night of November 19, 2006.[newsphoto]

The Beijing-Shenyang expressway, capital of China's northeastern Liaoning Province, didn't reopen until 9:33 a.m on Monday.

The Beijing Municipal Observatory has issued a yellow warning against the fog and reported the visibility to be as low as 500 meters.

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The visibility is between 300 meters and 600 meters on average and as low as 10 meters in some road sections, said Zhao Jinghong, a weather forecaster of Tianjin Municipal Observatory.

The visibility of Beijing Capital International Airport fell to 600 meters, resulting in some flights being delayed, especially flights heading to eastern Shandong Province, according to the Beijing Municipal Observatory.

Cold air on Monday night will bring fairly strong winds to north China and disperse the fog, the Beijing Municipal Observatory said.

The visibility in parts of east China's Shandong and Jiangsu provinces, north China's Beijing and Tianjin municipalities and northeastern China's Liaoning Province was a mere 200 meters.

More than 40 flights from Taoxian airport in Shenyang were delayed on Sunday.