IL pollen report
Chicago Pollen Report
Chicago's allergy season is compressed but intense. The city's famous park system and tree-lined neighborhoods produce heavy spring tree pollen, the lakefront moderates but doesn't stop the spread, and by late summer Chicago is squarely in the ragweed belt — one of the worst regions in the country for fall allergies.
Collection coming soon to Chicago
PollyMap is actively recruiting a verified local partner in Chicago. Be the first to know — or apply to be the partner.
While we find a local clinic
Test the air at your own home in Chicago
No allergy clinic is reporting from Chicago yet. Until one does, you can order your own PollyKit — a simple air sampler you hang outdoors or indoors. Send it back and the PollyKit Lab shows you exactly what's floating in your air.
- Pollen from local trees, grasses and weeds
- Airborne mold spores
- Dust mites and other indoor allergens
Hang it outdoors
See which pollen and mold are in your yard this season.
Or hang it indoors
Check bedrooms and living spaces for mold, dust mites and more.
What drives allergies in Chicago
Trees: oak, maple, and birch (April – May)
Chicago's spring tree season starts later than southern cities but hits hard. Oaks (Quercus), maples (Acer), birch, and the city's many elms pollinate heavily in April and May.
Grasses: Kentucky bluegrass and Timothy (June – July)
Lawns across the metro are dominated by Kentucky bluegrass, which along with Timothy grass drives a short, sharp grass pollen peak in early summer.
Weeds: ragweed (August – first frost)
Chicago sits in the heart of ragweed country. Ambrosia grows in every vacant lot, rail yard, and roadside, and August through October counts can be severe until the first hard frost.
Mold: summer humidity and leaf season
Humid summers lift Alternaria and Cladosporium counts, and mold spikes again when leaves fall and pile up through October and November.
Pollen patterns in Chicago
In Chicago, tree pollen — including Maple, Oak, Birch — typically dominates from late winter through spring. Bluegrass grass is the most common warm-season pollinator, and Ragweed drives the largest fall pollen load.
Top trees
- Maple
- Oak
- Birch
- Ash
- Walnut
Top grasses
- Bluegrass
- Timothy
- Orchard
- Rye
Top weeds
- Ragweed
- Lamb's quarters
- Pigweed
- Plantain
Top molds
- Alternaria
- Cladosporium
- Aspergillus
- Penicillium
Chicago pollen calendar
Typical monthly intensity across the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| tree | ||||||||||||
| grass | ||||||||||||
| weed | ||||||||||||
| mold |
Historical reports
Cities near Chicago
Explore pollen activity in nearby cities reported by the PollyMap network.
Frequently asked questions
What is the pollen count in Chicago today?
PollyMap publishes real, measured pollen counts for Chicago — collected with physical samplers and identified under a microscope. See the latest Chicago report on this page for current tree, grass, weed, and mold levels.
Is the pollen count high in Chicago right now?
Chicago pollen peaks in April–May (trees), June–July (grasses), and August–October (ragweed). The measured reports on this page show the latest real levels.
When is allergy season in Chicago?
Roughly April through the first hard frost: tree pollen in spring, grasses in early summer, and ragweed from late summer into fall. Mold adds to symptoms in humid stretches.
Does Lake Michigan affect Chicago pollen?
The lake breeze can briefly clear pollen near the shoreline, but it doesn't stop it — and Chicago's tree canopy and widespread ragweed keep counts high across most of the metro.
Are you an allergy clinic in Chicago? Claim your territory on PollyMap.
PollyMap is a local authority-building tool for allergy clinics, ENT practices, and any clinic that offers allergy care. By becoming the Official PollyMap Partner for your part of Chicago, your clinic gets credited on real pollen reports, receives ready-to-share weekly content, and becomes the go-to local expert patients trust.
We assign each partner a designated territory within the Chicago metro — like a franchise territory. Chicago has room for multiple partners, but once your area is assigned, it's locked to your clinic.
No clinic has claimed a territory in Chicago yet. The best areas go to the first clinics that sign up — once one does, that part of town is off the table for everyone else.
Chicagoland is the third-largest metro in the country — with neighborhoods and suburbs from Evanston to Naperville, there is room for many PollyMap territories. Lock in your area and own the local allergy conversation.
- Your clinic credited on every Chicago pollen report
- Weekly real-sample reports and ready-to-share content under your brand
- Locked territory — competing clinics can't claim your area
- Become the go-to allergy expert in your part of Chicago
Supported by PollyMap sponsors
Your business could be here
Reach local families checking real pollen conditions in their community.
Become a sponsorReport findings are based on reviewed sample data and are not influenced by sponsors.