Yesterday on 1 July 2011 the folks at Fort Valley (7300 ft), north of Flagstaff, woke up to an icy cold 31 degrees F. This didn’t last long, as the high temperature climbed 56 degrees to 87 F by afternoon.
http://www.rmrs.nau.edu/fortvalley/met/
In contrast, just 36 hours later on 2 July 2011 the temperature reached a sizzling 120 degrees F at Gila Bend (700 ft) and 121 degrees at East Mesa (1500 ft) coop sites after morning low temperatures in the high 70s.