Dear John and Jodi:
We do this every year. We have done it two years now with the Campinn.
1. I40 can be touch and go. If you want to not constantly watch the weather, go I10.
2. We tend to stay to the lower altitude areas so that it is warmer during the day. If it is very nice, we might try a higher altitude area.
3. RESERVE sites - NOW - for the Christmas weekend, the New Years Weekend, and the days in between. This may answer your question regarding Sedona. We weren't worried about this at first, as we thought if the parks were filled, we could use the national forest lands. It was a huge mistake. Because of rain, and the downsides/dangers of rain in the desert, we didn't feel we should use the national forest lands, it was an El Nino near, and I spent half the vacation desparately seeking camping sites and moving every night.
4. If you have solar and don't need an electrical hookup, there will be more and nicer sites to choose from. You will not be as much in a Big RV Ghetto. We have 120 panels and can easily stay parked for a week with no concerns even if the weather isn't ideal, but we don't use a refrigerator.
5. We drive to Bernalillo (adjacent to Albuquerque) and stay at the Coronado campground to transition from winter weather to the warm south. There is a great bike trail there *Del Bosque*, and it is year large bird preserve, but we use it as more of a utility stop and move on.
6. Here are some campgrounds we like. There are more, but like I said, we stick to the lower altitude for warmth (which unfortuneately cuts out a lot)
a. Catalina State Park, in the Tucson metro area. It is in town which may or may not be good for you. But if the weather is bad, it is nice to go to a movie.
b. Kartchner Caverns State Park, south of I10. The caverns are amazing and there are nice moderate hiking trails.
c. Patagonia state park. Not as pretty as some others - close spots, but this is a birder's paradise.
d. The Chiricahua National Monument. There are two campgrounds. The Cochise stronghold - incredibly beautiful. We have gone there repeatedly but are scared to camp there because you have to cross a stream to get in. There would be no turning around with the tear. Another downside is it is in the belly of a narrow canyon, and in December, it makes the days very short. The second is in the national monument - my favorite place of all for hiking. It is cold there - higher altitude and shade, but worth it if you have some warm weather.
e. Lost Dutchman State Park: Near Apache Junction. Great for hiking. Not the most quiet.
7. If you reserve at one of these for the Christmas week, generally you don't have to worry about weather. Then after that time period, you can explore more and pick spots based on the weather. e.g. if it is really warm you can go a lot more places.
I hope this helps.
Lorie