Need Advice for AT Section Hike in December

The trail could be snow free, have a light coat, or have drifts 5 ft deep.

It all depends. Hurricane Sandy buried the Smokies in several feet of snow last year very early in the season and stranded hikers, requiring rescues.

Your gear, and approach, has to depend on the the current trail conditions, and the forecast, with a bit of safety margin.

You will have to make reservations and stay in shelters. It wont be a problem for Dec.

I did that section last December. We left Davenport Gap in the morning, shorts no shirt. Severe thunderstorms hit and the temperature dropped. By the next morning it was 18 degrees with extremely strong winds, a few trees fell. The trail became ice and snow started. By noon we were at Newfound Gap with drifting snow. That was a huge change in just over 24 hours. So, bottom line, nobody can tell you what to expect other than it will change.

Also, check to see if the road to Clingmans dome is open. It is seasonal.

Why not check out Lineville Gorge? Its a nice areas and its lower. I would add one caveat, its a steep hike. If there is ice on the trail its not worth it. There is a visitor center and if its open they'd be able to tell you what the conditions were like.

Linville fire is 70% contained. Might want to look elsewhere.
I wish I had advice for you on the Smokeys.

Fire in Lineville Gorge? Bummer I hope the old growth forest survives.

You might consider the Art Loeb Trail. The first half is fairly low if I recall then it climbs up to some really nice balds and you can go up Cold Mountain if you want.

"Also, check to see if the road to Clingmans dome is open. It is seasonal."

Was not aware of that- will do.

I know the Smokies has really unpredictable weather, was just wanting to make sure that this wasn't a totally crazy idea. I think if the weather is moderate or average for that time of year, and IF the road to Clingman's Dome is open, we'll give it a shot, starting from the dome and going more or less downhill to the gap.

Another question, regarding camping at the shelters…..can you pitch a tent adjacent to the shelter if the shelter isn't full, or are you supposed to sleep IN the shelter? If the latter, I reckon a bivy will be in order.

BTW, I really appreciate the responses so far.

You must sleep in the shelters unless they are full to capacity, which is unlikely in December.

The weather will probably be fine for doing that section in December. Definitely check the weather before going, though. Honestly, though, its rarely pretty in December to my aesthetics unless there is snow. Expect short, gray days.
You are required to stay in shelters but you could easily set a small tent up inside the shelter if you want. There will probably be no one else there. But I would just sleep on the shelter platform. Its easier, there are 3 walls of wind block, and you won't have to carry a tent.
I did Davenport thru Clingman's and on to Fontana over four days this past September. The trail was in very good condition. Brace your knees for a long downhill from Cosby Knob to the bottom. Don't skip Charlies Bunion or Mt. Cammerer, two of the best views in the Smokies. Both are just a little off the main trail but well worth it.