At 6500 ft above sea level (which Grants, NM is), below freezing now happens at that elevation this time of year.
My corner of NM the last 4 yrs is about the same sea level and also has below freezing temps this week.
In that area, the difference between daily high and low is 35-40F easy. Its about half that where i live.
But you probably have low humidity which helps.
Ed