Ideas for January

I snowbirded to Florida for 3 years and never made reservations. All CG's leave a certain amount of sites for traveling RV'ers.

I'd pull in for the night and if I really liked the CG I would extend my stay a day or two and tell the CG mgr that I was looking for extended stay.

There was always a cancellation in each CG I pulled into. Some for one month, some for 3 months.

Doing it this way I never had to stay at a CG that I did not like.

I don't think you'll have trouble getting sites - those locales are not snowbird destinations because of the weather (and other factors)

Or join the crown at Quartzsite, AZ.

As you mentioned TX, Big Bend NP or Davis Mountain SP. Just over the NM border you could do Las Cruces.

We do two winter trips every year, a week each. One is the week of Christmas and the other is the week of March 10. We do the Florida Pan Handle (State Parks) in December, and South Carolina in March. Been doing this for several years now. We haven't found a bad spot yet in South Carolina (State Parks). We are State Park campers.

We do make reservations almost a year ahead of time for both locations.

Southern NM gets cold in the winter

Lots of dry/boondocking areas in NM....Gila and Lincoln NFs. They won't fill up.