Not sure about weather in Northern NM then but here are a few favorites.
Santa Fe: we've stayed at Trailer Ranch in town twice and enjoyed it (adults only.) On a bus line with frequent service, so you can leave the RV parked and have no parking hassles. Bus takes you to the Plaza, also the Farmers Market en route.
Taos: We had a good stay at Taos Monte Bello RV park. Drive the High Road to Taos from Santa Fe.
Abiquiu (Georgia O'Keeffe country): The Riana Campground on the lake is a nice COE park with low rates (half for senior pass), and can be reserved ahead.
Chaco Culture NHS: a World Heritage Site, has dry camping that now can be reserved online.