Wow, if we could predict the weather for a week to two from now, we'd all be rich!
The truth is that it'll probably be all of those things at various times during your cruise. The Caribbean tends to be tropical climate all year 'round, which means hot, sunny sometimes, overcast sometimes, and periods of rain showers that don't last very long. I'd be surprised if you encounter weather that's substantially different than that.
Have a great time!