Whatcom County, Washington
AQI 30 · Good30
Median AQI
43
90th Percentile
58
Max AQI
237
Days with Data
Ranked #21 of 31 counties in Washington (by median AQI, lower is better)
Monthly Median AQI — 2025
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30
Median AQI
43
90th Percentile
58
Max AQI
237
Days with Data
Ranked #21 of 31 counties in Washington (by median AQI, lower is better)
Click a bar to view that month's details