Peak fall color in Colorado’s mountains is on a “normal schedule”. It should occur the last two weeks of September and first week of October.
Last year, extreme drought forced peak color earlier than normal. Aspen trees were stressed and some leaves dropped early.
Take a look at the photo below from Grand Lake. It was snapped on 9/13/2021 by friend and photographer John Williams, who also has a photography shop on Main Street in Grand Lake.
Here is a rough timeline for peak color.