We cruised the Southern Caribbean last August (late in the month), and the weather was in the 90s. We had minimal rain (I think about 10 minutes total in St. Maarten.) I found it very humid inland, but on the ship and near the shoreline, the ocean breezes helped. Ivaro is correct about the sunscreen, too. Too many people on our cruise got sunburn early in the trip because they didn't wear sunscreen.