We were at CSS last may and will be returning again this May. Daytime: Mid-80's, plenty of sun with periods of variable clouds, got a good shower one afternoon (just stayed on the beach under a palapa. Night: Very comfortable in the 70's, no rain. Hope your plans work for you,
We were there at the very end of May and the weather was really nice. Only rained a little one day. Definitely a bit hot in the direct sunlight but the water was perfect and a nice way to cool off. We always requested a table under a ceiling fan at the open-air restaurants -- definitely helped. It was very humid but didn't affect things much at all! You'll have a great time!
This will be our first time to the island. Coming from Kansas, anything out of here will be super. Been to Cancun, Cozumel, it does rain in the morning, no worries. Hope to meet some new friends, will be arriving May 31st-june 6th.
USN family here. You can expect high 80's in the daytime, and low to mid 70's at night. May is generally before hurricane season, so you may see some buildups, and occasionally, one may pass through, but you typically don't get those all day cloudy, soaking rains that we see in the eastern half of the US. If the rain comes, just go to the bar! LOL