My suggestion is
Desert Trails in SW Tucson. While the sites are not the most spacious around the rates are very reasonable, the unusual layout makes it quite comfortable. The park is quiet with friendly owners and residents.
You can walk right out into the desert from the park - into Tucson Mountain Park and Saguaro West National Park - and go as far as your stumps can carry you on good trails.Flat desert or mountain trails, whatever turns your crank.
Tucson is relatively high (2.450 feet at Desert Trails) so the nights are cool (usually 40's) and the days are warm (60's and 70's). January is their secondary "rainy season" but that means less than an inch since they average about 8" a year. So rain is rare, although this El Nino winter may mean more rain than usual.
We will be there in our usual spot for the 7th winter sometime in November
