Cool Morning In Southeast Arizona

Clear skies and light to calm winds led to a crisp, cool Fall morning. Here at the house the low temperature fell into the 30s (39F) for the first time this Fall, while it was a mild 50F at the airport. I see that Douglas, down in the far southeast and at 4000+ ft elevation dropped to 32F - the first freezing temperature I've noted this Fall. Interesting differences at the two closest RAWS sites - Mt. Hopkins (7120 ft) had a low of only 48F but Rincon (8209 ft) had a low of 37F. The site at Mt. Hopkins reported winds of 10 mph or more during the night and so there was little radiational cooling at that exposed site.