Welcome to cruise-chat JE. The caribbean is nearly always at or around the 80s. Summer months mid to high 80s and high 70s to low 80s other times of the year. Depending on what the climate is like where you are, that could seem very hot or mild. I'm in Houston so it's refreshing temps in the summer for me vs high 90s and sometimes hotter here with 90%+ humidity here much of the year. There is nearly alway a sea breeze, I don't think you'll have many issues if you bring some shorts and short or sleeveless things. Have a great cruise!