Heat Invades Cool Heights Over Arizona Desert - New York Times
“SUMMERHAVEN, Ariz. — High above the desert floor, this little alpine town has long served as a natural air-conditioned retreat for people in Tucson, one of the so-called sky islands of southern Arizona. When it is 105 degrees in the city, it is at least 20 degrees cooler up here near the 9,157-foot summit of Mount Lemmon.”