China issues yellow alert for fog

BEIJING - China's national observatory on Friday issued a yellow alert for fog in the country's northern and central regions.

From Friday to Saturday, there will be thick fog in parts of the Beijing-Tianjin-Hebei region as well as provinces of Henan, Hubei, Sichuan and Hunan. In parts of Hebei, Hunan and Hubei, the fog will reduce visibility to less than 500 meters, the National Meteorological Center said.

In extreme cases visibility may fall below 200 meters in those regions, it added.

The center said drivers in affected regions should slow down to safe speeds.

China has a four-tier color-coded warning system for severe weather, with red being the most serious, followed by orange, yellow and blue.