Harford County, Maryland
AQI 43 · Good43
Median AQI
61
90th Percentile
143
Max AQI
303
Days with Data
Ranked #14 of 16 counties in Maryland (by median AQI, lower is better)
Monthly Median AQI — 2025
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43
Median AQI
61
90th Percentile
143
Max AQI
303
Days with Data
Ranked #14 of 16 counties in Maryland (by median AQI, lower is better)
Click a bar to view that month's details