When Fall Colors starts peaking at the Rocky Mountains

Now, as we reach mid to late September, it’s that time again: Valleys and mountain slopes at higher elevations across the Rocky Mountains are painted in gold. This region - stretching from Grand Teton National Park through Rocky Mountain National Park down to the San Juan Mountains near Durango and Telluride - offers some of America's most spectacular fall color displays, thanks to extensive aspen forests beneath snow-dusted peaks. The aspen leaves display a stunning variety of colors ranging from brilliant golden yellow to vibrant orange and, occasionally, deep crimson red. While temperatures also play a role, their color transformation is primarily caused by the shortening of daylight hours in late summer. But cool nights below 45°F accelerate the change and help trigger the striking scarlet tones. Those particularly vivid reds occur when, after photosynthesis stops, excess sugars become trapped in the leaves at low temperatures and are converted into red pigments called anthocyanins.

Peak colors typically begin in mid-September at higher elevations and progress through early October, moving from north to south across the region. But forecasting the peak of fall color is challenging, given the rapid weather shifts and elevation-driven microclimates in the Rocky Mountains. Colorado alone is home to 58 "Fourteeners", peaks exceeding 14,000 ft (approximately 4,300 m). Climate change has also been affecting the process, tending to delay the peak by roughly a week over the past two decades. Nevertheless, colors can still arrive up to two weeks early or settle in later than the "new normal".

The current foliage status
To help plan for peak viewing, here are a couple of regularly updated resources that track the progression of fall colors with current images and webcams for real-time conditions:

• Webcam at the Grand Teton National Park:
  https://www.nps.gov/grte/learn/photosmultimedia/tetonrangewebcam.htm 
• Updates for the San Juan Mountains around Ouray and Silverton:
  https://www.fs.usda.gov/r02/sanjuan/conditions/sjnf-fall-colors-report
• Updates for Telluride, Dallas Divide, Last Dollar Road and Trout Lake:
  https://www.telluride.com/discover/blog/fall-foliage-update/
• Webcam at the famous Maroon Bells near Aspen/CO:
  https://www.aspensnowmass.com/four-mountains/aspen-highlands/mountain-cams
• Updates for the area around Crested Butte and Kebler Pass:
  https://travelcrestedbutte.com/crested-butte-fall-color-updates/

We love shooting fall colors. If you are interested, please feel free to check out our other fall foliage images from the Rocky Mountains (most are from 2022-2024, with a few dating back to 2006).