Clark County, Illinois
AQI 36 · Good36
Median AQI
49
90th Percentile
87
Max AQI
267
Days with Data
Ranked #3 of 23 counties in Illinois (by median AQI, lower is better)
Monthly Median AQI — 2025
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36
Median AQI
49
90th Percentile
87
Max AQI
267
Days with Data
Ranked #3 of 23 counties in Illinois (by median AQI, lower is better)
Click a bar to view that month's details