Well, ask the folks who were at WDW the first week in December 2010 how warm it was. We were wearing winter jackets, hats, and gloves and still freezing while we waited for the dancing lights. Of course, what feels cold to us Floridians may not feel cold to others. It starts feeling really cold to me when it gets about 40 or below, especially if it's windy. The one time I have seen snow flurries since I moved to Florida more than 30 years ago was in December. We had rolling blackouts one December because the power company couldn't keep up with the usage in the cold weather.
It really all relates to what is happening up north. If the winter starts early up there, then we start getting cold fronts early down here. Our coldest months are usually January and February, but it's certainly possible to have cold weather here in November and December, and you don't always have a lot of advance warning that a real cold snap is on the way.