Lake Zurich, Illinois Air Quality

Lake Zurich air quality today — the AQI, the main pollutant, and whether it’s safe to exercise outside right now

Lake Zurich, IL · Air quality right now

The air quality index in Lake Zurich, IL is 36 (Good) right now — safe for outdoor activity.

Is it safe to be outside in Lake Zurich today?

AQI 36 Yes — air quality is Good

Air is clean — great for outdoor activity.Main pollutant: PM2.5Observed 10:00 AM CDT

Pollutants right now

ExerciseOK to run — no air-quality limits on outdoor exercise.

How to read Lake Zurich’s air quality

Guides: The AQI Scale, Explained · Air Quality Alerts, Decoded · How to Read a Wildfire Smoke Map · Why Wildfire Smoke Travels 1,000 Miles.

Air quality over time in Lake Zurich

Across the EPA’s county records from 2020 to 2025, Lake Zurich’s cleanest year was 2020 (median AQI 39) and its most polluted was 2021 (median AQI 42); the typical (median) day has held roughly steady since 2020.

Lake Zurich’s county air-quality record by year — the median and days in each AQI category, from the EPA’s Annual AQI by County summaries.
YearMedian AQIUnhealthy+Main pollutantUSGModerateGood
2020391Ozone1031199
2021420Ozone955180
2022391Ozone241199
2023421Ozone1347182
2024400Ozone539201
2025390Ozone332196

“USG” is Unhealthy for Sensitive Groups (AQI 101–150); “Unhealthy+” combines the Unhealthy, Very Unhealthy, and Hazardous days. In 2024 the EPA tightened the annual fine-particle (PM2.5) standard to 9 µg/m³ from the previous 12 µg/m³, so counties near the old limit read worse against the new one. Source: EPA AQS annual summaries, 20202025.

Frequently asked

What was the worst year for air quality in Lake Zurich?
In the EPA's 2020–2025 county records, 2023 had the most days above AQI 100: 14 days (13 Unhealthy for Sensitive Groups, 1 Unhealthy or worse). It also had the highest median AQI, 42.
How many unhealthy air days does Lake Zurich have?
Across 2020–2025, 3% of the days reported for Lake Zurich's county had an AQI above 100 (45 of 1447), about 8 days a year. 2025 had 3 days.
What's the main air pollutant in Lake Zurich?
Ozone: it drove Lake Zurich's county AQI on the most days in every year of the EPA's 2020–2025 records.