Santa Fe will be quite cold in December usually. It's high desert, so don't let the whole "desert" thing fool you. Snow is also a possibility as boxermom mentioned. There are some well loved spas in Santa Fe though and you can also day trip to a couple interesting places from there.
If you're looking for a short flight, there's always Portland, Seattle, or San Diego. A little bit longer and you could do Dallas (nice spas, great shopping) or one of the other larger cities in TX (haven't really been to those much, so I don't have any opinions on them).
If you're looking for a short flight, there's always Portland, Seattle, or San Diego. A little bit longer and you could do Dallas (nice spas, great shopping) or one of the other larger cities in TX (haven't really been to those much, so I don't have any opinions on them).