Aside from the pools being heated, as others have stated, it's not unusual for the temps in Central Florida to be in the 80's and even push 90 well into December. I remember Christmases growing up in Florida where we were sweating in shorts and t-shirts running around in the front yerd. It will be less humid and the nights will get colder, but it might still be fairly warm out while you're there.
There's no forecasting these things until you get closer to your trip, of course, but I'm just throwing the possibility out there, as it is both possible and even probable.