I'm currently in the Atlanta area and we're not supposed to see overnight freezing weather again until Monday night. Saturday and Sunday temps are forecasted to be in the low 70's, with rain on Sunday. When going through Atlanta, go straight through. Stay in the dead center of the expressway, as the right lanes will disappear on you. There's not a lot of good camping near I-75 close to Atlanta. If you don't stay near Chattanooga, you may not find a good campground until you get down to High Falls State Park, which is only a couple of miles off of the interstate near Jackson Georgia (before Macon). Once you get over the mountain at the Tennessee/Kentucky border, you should be good to go. You have a pretty good grade coming into Chattanooga, but I don't think you'll have any ice problems there.
When going home, it may be good to have the Camping World that is between Macon and Atlanta to re-winterize your rig. You can probably check CW site for the location and call them for a reservation. You could probably even stay the night there.
Have a great trip.
