Colusa County, California
AQI 39 · Good39
Median AQI
54
90th Percentile
96
Max AQI
265
Days with Data
Ranked #12 of 46 counties in California (by median AQI, lower is better)
Monthly Median AQI — 2025
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39
Median AQI
54
90th Percentile
96
Max AQI
265
Days with Data
Ranked #12 of 46 counties in California (by median AQI, lower is better)
Click a bar to view that month's details