China renews yellow alert for thick fog

China's national observatory on Saturday renewed a yellow alert for thick fog that will shroud parts of the country.

Thick fog enveloped the provinces of Hebei, Shandong, Henan, Anhui as well as the city of Tianjin Saturday morning, with visibility in parts of Hebei, Henan and Shanxi to be reduced to less than 50 meters, the National Meteorological Center said.

It suggests drivers in affected regions slow down, while airports, expressways and ports take appropriate safety measures.

China has a three-tier color-coded warning system for fog, with red being the most serious, followed by orange and yellow.