I have carried them on a Class 8 truck but never in all my years of driving CO did I ever put them on. CO takes good care of their highways and there are signs that tell you if the chain law is in affect and what "grade" snow chains or snow tires or tires with studs. You can expect any temp you can dream of. 70s to 0. It can snow any month in CO. Yes it's possible. I don't mean to be mean but doesn't make sense for me to plan a trip for you does it? You probably have to call around.
http://tirechain.com/COLORADO-ROAD-CONDITIONS.HTM