Is Arizona cold?

In some places. We live in Flagstaff (7000 ft.). It snows up here in winter (we got 9 ft. one week last winter). However, the sun comes out after the storm and melts a lot, but not nearly all of the snow. In winter, daytime highs can be in the 40s but it can go down into the teens and single digits at night (This is the high desert) The same is true north of here, including the Grand Canyon. Remember, services on the North Rim are closed from mid October until some time in the spring. It is very cold up there and in winter the roads can be closed.

On the other hand, in summer when Phoenix is an unbearable 115 degrees, the daytime high is in the eighties in Flag. Very nice.