Up in the mountains it snows in May, for sure.
From Channel 4, in Denver:
The new snow will likely create additional delays in opening roadways such as Trail Ridge Road through Rocky Mountain National Park. Road crews try to open as many passes as possible in Colorado’s high country ahead of the busy Memorial Day Weekend, but are facing extra challenges this year due to a deep snowpack and the current forecast.

Snowplow operator above Milner Pass on May 9, 2019. probably about 11,000 feet.
That white stuff on the side is snow, for those of you who've never seen it before (Florida folks are so unsophisticated)
Here in Colorado Springs, though, (6,700 feet at our house) snow is not so common in May, but it does happen.
https://www.currentresults.com/Weath...n-averages.php
I would disagree with what the article says about snow amounts in the winter, however. I think that's down lower at the airport (6,100 feet elevation) where temps are usually about 5 degrees higher. Those few little degrees can make a real difference whether the snow piles up or melts.
Monument, Colorado, just a few miles north of us and a bit higher than we are, gets an average of 96 inches of snow a year, compared to the Springs at 38 inches. We're sorta in the middle.