Which is colder, Hong Kong or Xiamen?

it's cold in Xiamen. The average winter temperature in Xiamen is 18℃~25℃, and that in Hong Kong is 2℃~25℃. Comparatively speaking, Hong Kong is slightly warmer than Xiamen. Hong Kong belongs to the Hong Kong Special Administrative Region with subtropical climate, which is called Hong Kong for short. It is located in the south of China, east of the Pearl River Estuary, across the sea from Macau to the west, adjacent to Shenzhen to the north and Wanshan Islands in Zhuhai to the south.