Yes, Jack Frost made a quick visit to Tucson. It was actually below freezing last night! The mountains had snow but all we got on the lowlands was a wee bit of frost on some of the plants. Here's a fence post with a dusting of snow.
I'm a transplanted New Yorker who loves the Tucson climate. On New Year's Day I have a bit of fun calling my (snowbound) east coast friends to announce that I'm drinking coffee while sitting on my patio. (: