Effingham County, Illinois
AQI 35 · Good35
Median AQI
46
90th Percentile
71
Max AQI
211
Days with Data
Ranked #1 of 23 counties in Illinois (by median AQI, lower is better)
Monthly Median AQI — 2025
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35
Median AQI
46
90th Percentile
71
Max AQI
211
Days with Data
Ranked #1 of 23 counties in Illinois (by median AQI, lower is better)
Click a bar to view that month's details