Sorry, I don’t know the other Colorado track schedules; otherwise I would mention those as well. I’m sure you can inform us with a reply post.
The Colorado Karter Calendar is up to date with the all the series I could find that ran races in Colorado, including the SKUSA race in Utah.
That calendar is a Google calendar, which means you can import it into your favorite calendaring tool, including iPhones, Android, Outlook, or any calendar tool that supports iCal.
Post any events on the general forum, I check regularly to keep the calendar updated.