I live in the Pensacola area, and we get several nights below freezing here during the midst of winter. I have a small chicken tractor that has straw in it and a larger cooper that my husband and I will cover with a tarp to keep the wind off the girls during the cold nights. Thus far, they have all fared just fine with no problems. They are incredibly tough birds and don't require any supplemental heat unless it gets below zero, in my opinion. The coldest I can recall it getting here is about 5 degrees one very cold winter, and in 2013 when we had our freak ice storm here - the girls did not like walking around on the cold ice! Can't blame them - neither did I!
I'd just ensure that they are warm enough if you have a cold snap and have a way to give them adequate shelter for those admittedly few times it gets cold and nasty during the winter.
We often say that we live in Lower Alabama rather than Florida in the western panhandle region!