I've never been the last week on Jan. This will be a first for us.
We have been in early January '02, and it snowed on our the drive down from my sister's house in ATL! We needed hats and gloves one day, but then a few days later, we were swimming because it got up into the 70's. Weird!
We were there over MLK weekend in Jan '08, and it was very warm. We needed shorts and such. So I guess, when traveling in Jan. you need to pack for dressing in layers! We're New Englanders, so a little cold and ice doesn't scare us!