We stayed in a cabin outside of Red River in the upper valley. Red River Real Estate and Bandanna Properties will rent the cabins outside of town. We've been renting from these two companies for years.
The temps will vary where you are, of course. If you are on the Rio Hondo where it hits the Rio Grande or on the Cimarron it may get up to 90. But above the town of Red River or in the Valle Vidal on the Costilla the temps will range between about 70 and 35. It will sleet on you and the temp will drop 25 degrees in a minute or two, at least. Be prepared!
Joe