BEIJING - China's national observatory maintained its blue alert Tuesday, after a cold front hit parts of central and east China.

Temperatures are expected to remain near freezing in many southern Chinese provinces, the National Meteorological Center (NMC) said.

Cities including Changsha, Hangzhou, Hefei, Guiyang, Nanchang, Nanjing, Shanghai, and Wuhan saw their temperatures drop below zero degrees Celsius, according to the NMC.

Within the next 48 hours, heavy wind is expected in parts of Gansu, Inner Mongolia, Shandong, and other north China regions, while southern China will see rain and snow.

The NMC advised residents to take precautions against the cold weather and icy roads.

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