A sanitation worker's hat is covered with frost as temperature plunges to minus 30 C in Northeast China's Harbin on Thursday. [Photo/Chinanews.com]

In Harbin, water transforms into ice as soon as it touches the air. [Photo/Xinhua]

A woman walks beside West Lake as the first snow fell in East China's Hangzhou on Thursday. [Photo by Long Wei/Asianewsphoto]

In Nanjing, East China's Jiangsu province, the City Wall of Ming Dynasty (1368-1644) is covered with snow on Thursday. [Photo by Xu Congjun/Asianewsphoto]

Ices float on a section of Yellow River in East China's Shandong province on "Major Cold", the last solar term in lunar calendar which often means the lowest temperature in a year, on Wednesday. [Photo by Zhang Binbin/Asianewsphoto]

A monkey in Beijing Zoo curls up under a piece of sackcloth as Beijing experiences the coldest days in the year. [Photo by Feng Yongbin/Asianewsphoto]

A panda in zoo plays in the first snow in Wuhan, Central China's Hubei province, on Thursday [Photo by Jin Siliu/Asianewsphoto]

Lushan Mountain in East China's Jiangxi province is blanketed by heavy snow on Thursday. [Photo/Chinanews.com]

Vegetable racks in a market in East China's Hangzhou are empty on Thursday as people rushed to stock food in response to the cold snap. [Photo by Xu Kangping/Asianewsphoto]