McLean County, Illinois
AQI 44 · Good44
Median AQI
69
90th Percentile
154
Max AQI
273
Days with Data
Ranked #16 of 23 counties in Illinois (by median AQI, lower is better)
Monthly Median AQI — 2025
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44
Median AQI
69
90th Percentile
154
Max AQI
273
Days with Data
Ranked #16 of 23 counties in Illinois (by median AQI, lower is better)
Click a bar to view that month's details