The map isn’t too far off for July[1] considering how far Australia is from the Equator[2].

My area is similar to Sydney in your map. For Denver it’s the elevation that’s exposing them to more UV rays.

[1]https://www.epa.gov/sunsafety/sun-safety-monthly-average-uv-...

[2]https://www.reddit.com/r/MapPorn/comments/cd1t54/relative_la...

Yep, this—we aren’t as close to the equator, but there’s less atmosphere to filter UV. Not so much in terms of beach days, of course, so sunburns here tend to be less than full-body.

All that said: a daily mean of 13-14 is past what we’d see here—and yeah that is some serious burning.