Do you need specific dates? I would avoid Christmas/New Years, MLK Day and President's Day weekends.
Also, do you have to go to CO/WY? You may also want to check other destinations such as Lake Tahoe (via RNO or SMF), Montana, SEA, YVR, or YYC.
Edit: Also don't forget New Mexico.
Last edited by Lost; Oct 2, 2014 at 9:15 pm