bjr8826,
I'm an ex-Dallasite, and as noted previously, it could drop down as low as the 40's here in FL during that time of the year...just now way to be sure.
If Cancun (or some other cities in Mexico) are to your liking you should be able to get some really good deals to Mexico on FunJet. If you have a Dillard's card, even better, you can charge it on that.