Fall is almost here, and you may have already noticed one or two trees changing colors in your neighborhood.
But when will the autumn foliage reach its peak in Illinois?
Here’s what experts say.
Why do leaves change colors in the fall?
Though many people think cold weather is solely responsible for the change in leaf color, it’s actually caused by chemical processes, according to the National Weather Service.
During the fall, the sunlight decreases in intensity and duration and temperatures cool, causing leaves to stop their food-making process. As a result, the chlorophyll in the leaves breaks down, the green color disappears and the yellowish colors or other pigments already in the leaf become visible.
Others are reading: Tired of hot weather? See what Old Farmer’s Almanac, NOAA say about Illinois fall forecast
When will leaves change color in Illinois?
The Illinois Fall Foliage Map says leaves are expected to start changing towards the end of September, reaching their peak color in late October. The map predicts the shift will occur first in northern and western Illinois before reaching the rest of the state. The colors will likely be past their prime by mid-November.
The Illinois Fall Colors Trip Planner, powered by the Illinois Department of Natural Resources, shows a similar timeline, with the change in colors gradually shifting south over time. The planner predicts colors will reach their peak in the second week of October in northern Illinois, late October in central Illinois and the last week of October in southern and southwest Illinois.
Meanwhile, the Old Farmer’s Almanac says foliage will start to change in the Midwest by late September, with the leaves in some areas passing their prime by Oct. 4. This will be paired with a cooler and drier autumn this year, according to the almanac.
Best places to view fall foliage in Illinois
Here are some of the best places to view the vibrant color changes, according to Enjoy Illinois:
Marina Johnson contributed to this article.
This article originally appeared on Journal Star: Illinois 2025 fall foliage forecast: See peak times, best spots to view colors