✔ 最佳答案
I cruise the Caribbean every December and the weather is always very nice, temps in the 80's during the day and maybe 65-70 at night. But you will likely be inside a temperature controller environment on ship at night so no need to worry unless you want to spend time outside. A light jacket, sweater or wrap will do for that. Yes bring short sleeves for the days.
Water temperatures will be great for all types of water s;ports and swimming and diving.