When Fall Foliage Will Peak In Illinois: Map

ILLINOIS — While some are holding tight onto the last days of summer weather and sunshine past the dinner hour, others are ready for all things fall.

And as hints of red, orange and yellow start speckling Chicago-area trees, fall aficionados are sure to rejoice. For those fall lovers — those who are ready to pull out their cozy sweaters and grab a pumpkin spiced latte — the 2025 Fall Foliage Prediction Map should give them hope that cooler, crisper and more colorful days are ahead.

• Peak Fall Foliage In Illinois: When And Where To See The Changing Leaves

Created by SmokyMountains.com, a travel group, the tool is also "meant to help travelers better time their trips to have the best opportunity of catching peak color each year."

As of Thursday, all of Illinois is showing "little to no color." The map is easy to use; you can use the slider at the bottom to scroll to the right to see when peak fall foliage is expected near you. Leaves haven’t started changing yet in green areas, and the brown color means foliage has passed its peak.

According to the Illinois Department of Natural Resources, Illinois' fall color season lasts for several weeks. The leaf changing normally begins in northern Illinois counties by the third or fourth week in September; the second week in October for central Illinois; and the last two weeks of October for the southern part of the state.

"The peak of fall color in Illinois normally occurs by mid-October in northern and central Illinois and by late October or early November in the southern third of the state," according to the IDNR.

The SmokyMountains.com released its Fall Foliage Prediction Map in 2023. The map uses a refined data model that takes into consideration factors, including historical and forecast temperatures and precipitation, the types of trees prominent in specific geographic areas, and real-time user reports.

Like any meteorological forecast dependent upon weather variables, leaf predictions aren’t always 100 percent accurate, but the map does give Illinois leaf-peepers a pretty good shot at seeing autumn leaves when they turn their most blazing reds, vibrant orange, and sunny yellows, map creator David Angotti said in a news release in 2023.

Angotti, an expert in statistics and a former airline transport pilot, used his understanding of weather patterns and meteorological tools to create the predictive map in 2013 as a tool for visitors to the Smoky Mountains who wanted to time their trips to the fall foliage peak.

As data collected in subsequent years has been added to the model, it has become a go-to tool for “tens of millions of people use our map each year to plan vacations, weddings, and photography trips,” Angotti said.

“What started as a fun side project quickly became the most respected nationwide fall leaf map and one of the best fall resources in the country,” Angotti said.

Where to Check Out Fall Foliage

Enjoy Illinois — the official website for the Illinois Office of Tourism — shared some great spots to visit as fall colors change in the Chicago area in its own interactive fall foliage tracker. Among those are:

Northern Illinois

Estimated fall foliage peak times are expected in the second week of October.

• Millennium Park, Lincoln Park and Jackson Park in the city of Chicago.
• Morton Arboretum in Lisle, Chicago Botanic Garden in Glencoe and Anderson Japanese Gardens in Rockford.
• "Galena, an idyllic river town surrounded by tree-lined hilltops, is a beloved destination for fall foliage seekers," according to Enjoy Illinois.
• Horseshoe Mound Preserve and Mississippi Palisades State Park are also great options.
• "Visit Starved Rock State Park in Oglesby to see waterfalls and colorful, tree-covered bluffs along its 15 miles of hiking trails," according to Enjoy Illinois.

Central Illinois

Estimated fall foliage peak times are in late October.

• Places to visit include: Prairie Fruits Farm & Creamery in Champaign; the Great Pumpkin Patch in Arthur; the 1,517-acre Allerton Park in Monticello; and the "natural splendor around beautiful Lake Decatur, including the Rock Springs Nature Center."

Southern Illinois

Estimated fall foliage peak times are the last week of October.

• "Alton to Grafton along the Great River Road during peak fall color season is breathtaking. Stop at Pere Marquette State Park at the confluence of the Illinois and Mississippi Rivers and, if you're brave, try Grafton Zipline Adventures for a stunning view from hundreds (or thousands!) of feet in the air," according to Enjoy Illinois
• A trip to Shawnee National Forest — with a great overhead view from Garden of the Gods — is worth a stop this fall. More outdoor trails can be found at Giant City State Park and near Carbondale. The Shawnee Wine Trail is a great option as well.

What Causes The Different Colors?

Beta-carotene, the same pigment that makes carrots orange, reflects the yellow and red light from the sun and gives leaves an orange hue. (Beth Dalbey/Patch)You may remember from science class that the color change all starts with photosynthesis. Leaves constantly churn out chlorophyll — a key component in a plant’s ability to turn sunlight into the glucose it needs to thrive — from spring through early fall. Those cells saturate the leaves, making them appear green to the human eye.

But leaves aren’t green at all. Autumn is the time for leaves’ big reveal: their true color, unveiled as chlorophyll production grinds to a halt. The colors in fall’s breathtaking tapestry are influenced by other compounds, according to the national park’s website.

Beta-carotene, the same pigment that makes carrots orange, reflects the yellow and red light from the sun and gives leaves an orange hue.

The production of anthocyanin, which gives leaves their vivid red color, ramps up in the fall, protecting and prolonging the leaf’s life on a tree throughout autumn. And those yellows that make you feel as if you’re walking in a ray of sunshine? They’re produced by flavonol, which is part of the flavonoid protein family. It’s always present in leaves but doesn’t show itself until chlorophyll production begins to slow.