I read that People are leaving California by the thousands=Take your Prius with you!!!

It depends on who you ask.

According to Wikipedia the coldest town in Colorado is Fraser.
Fraser, Colorado - Wikipedia

According to this other site Gunnison is the third coldest in the country, after Barrow, Alaska and International Falls, Minnesota.
Top 5 Coldest Places in America – Air Conditioning & Heating Repair Maintenance (wordpress.com)

Many days the temperatures are the same in both towns. But Alamosa may have a lower average temperature. The San Luis Valley, where Alamosa is, is also just over North Cochetopa Pass from the Gunnison Valley, so they're not that far from each other and are very similar geographically.

Alamosa does seem to have a better growing season, or at least they grow a lot more than just hay like in Gunnison. Alamosa grows lettuce and potatoes, for an example.

 

In my experience, Leadville, CO, gets pretty uncomfortable

 

Alamosa, Gunnison, and Fraser all still remain in my memories as cold spots from when we lived in Colorado. Leadville, too, to some degree. (Pun not intended, but enjoyed. LOL!)

 

South Park isn't as cold, although it was there where I was outside in -52°F weather. The problem there is the wind always blows which makes it feel even worse.

Some people say that Colorado isn't that bad because it's not a humid cold. But in reality, once you get down to -20° or so humidity doesn't matter because the air just can't hold the humidity any more. It can be 100% humidity and dryer air than the Sahara. Personally I'd take 30°F humid cold over -40°F windy cold any day.

My mother was born in Leadville.