The cross-check has clearance enough for studded tires and honestly I don't know how much you'd really need them. I use to work for a company based in Denver that also had a nice facility in Boulder. I'd spend weeks at a time in the Boulder office during the winter and I was surprised by the lack of snow. It definitely did snow, but it didn't stick around.

All in all I'd say the winters were pretty mild, but then I'm used to bad winters.

I didn't spend enough time in Denver for it to leave much of an impression but FWIW I liked the Boulder area. You could do a lot worse.