I live in the Phoenix area but there are a few things that are similar. Yes, it is hot in the summer but because Arizona doesn't do DST, the sun comes up between 5 and 6 AM - which is a perfect time to ride. The weather is nice and you can get a lot of riding in. Until I retired a month ago, I did most of my riding in the summer

Secondarily, Tucson is well known as a bicycling hot spot. Last Saturday was the Tour de Tucson where 9,000 riders took part in rides of 109, 80, 66 or 35 miles. I actually like the Phoenix area better for rides because there are more bike paths but if you go out to the bicycling magazine site you'll be able to see some additional rides.

Tucson is a lovely city - with a great climate and an excellent University.