I haven't been there in a few years. At high altitude you should always expect rain/hail...all the bad stuff. It would depend on the way you want to travel there. If you go through the Rocky's I would expect it, if you go north then drop down into Utah lesser of a chance. (what fun would the be:nojoke

But, there's always a but, the weather has been unpredictable this year to say the least.
When I was still active duty, we would go to Colorado Springs twice a year to teach pilots advance flying technics at high altitude and mountainous terrain. In the fall, the weather would change in the Rocky range by the minute it seemed. We would takeoff just to go see how the weather was. Then we would decide to push or return to base.
I'm looking at heading that way next year. Let me know how it goes.
Tree