Is Beihai cold in winter or Xuwen cold in winter?

Beihai is very cold in winter. The lowest temperature in winter in Beihai is 5 to 10 degrees. The lowest temperature in Xuwen in winter is 18 to 20 degrees. So the North Sea is very cold in winter. Beihai is a prefecture-level city in Guangxi Zhuang Autonomous Region, located at the southern end of Guangxi Zhuang Autonomous Region and the northeast bank of Beibu Gulf. Xuwen county, which belongs to Zhanjiang City, Guangdong Province, is located at the southernmost tip of Chinese mainland, with Qiongzhou Strait in the south, Hainan Island across the sea, South China Sea in the east, Beibu Gulf in the west and Leizhou City in the north.