Temperatures in Guangdong Province dropped to their lowest levels for the same period in more than 30 years early Friday morning, according to Guangdong Meteorological Center.

Temperatures in north Guangzhou dropped to minus 3 to 1 degrees Celsius Friday, and on the expressway linking Beijing to Zhuhai, temperatures dropped to minus 5.3 degrees Celsius.

The freezing weather caused traffic to pile up on the north Guangdong section of the Beijing-Hongkong-Macao expressway Friday morning, after it reopened Thursday afternoon, said Guangdong's traffic department.

Parts of the Beijing-Hongkong-Macao expressway were covered with ice and were closed early Thursday morning, said the publicity department of Yao Autonomous County of Ruyuan.

Authorities issued a yellow warning in five counties and cities in Guangdong, including Lechang, Ruyuan and Yangshan, saying ice on roads could cause traffic congestion over the next 12 hours.

Guangdong Meteorological Center forecast temperatures in Guangdong would start to climb Sunday.

Meanwhile, many northern Chinese cities already hit by the cold front reported the coldest temperatures in a decade .

In an extreme case, temperatures in Hulunbuir City in north China's Inner Mongolia Autonomous Region dropped to minus 46 degrees Celsius.