The weather forecast says it will rain in Hainan.

Have you already left? It is hard not to rain these days. Sanya is very hot. It won't affect. But there was a shower on the evening of the 22nd. I suggest you travel to Hainan after Tomb-Sweeping Day. There are many people on May Day. You can come before that. It was still Tomb-Sweeping Day, but it didn't rain much afterwards.