Hainan is the warmest city in China, there is no season winter, summer all around the year. It's quite a place for China coastal tourism maybe someday you could take a visit in Hainan city, you will remember it forever.
What City In China Has The Warmest Winter?
To get most accurate information, might be best to go to bing.com a search engine and key in your answer there. I find google takes all day