Southern Arizona No problem even in Tonto National forest or Lost Dutchman State park. Fiesta Grande in Casa Grande, Az and Pichacho RV park as well as other private RV parks will welcome you
IN Texas along the gulf you will have Galveston Island State park right on the gulf as well as many opportunities to dry camp right on the beaches for a night or 2.
Quartzite in January would be good for a night or 2. You basically pull out into the desert and set up camp. It is quite a show.
I did it in a tent for 2 months