Smoke: keep one room clean
Shut the windows and run an air purifier sized for the room.
Wildfire smoke guide →Air quality in Alaska, county by county
5 Alaska counties have enough EPA monitor data to count bad-air days. Weighted by population, they averaged about 6 days a year from 2021 to 2025 when the air was unhealthy for sensitive groups or worse.
Every Alaska county with monitors
Most bad-air days first. 4 have a full report. Compare with the worst and the cleanest counties in the US.
| County | Bad-air days a year | |
|---|---|---|
| Fairbanks North Star BoroughFairbanksWinter particles | 31.6 | |
| Matanuska-Susitna BoroughWasillaWinter particlesozone not measured | 1.2 | |
| Anchorage MunicipalitySmokeozone not measured | 0.8 | |
| Juneau City and BoroughRarely badozone not measured | 0.2 | |
| Denali BoroughRarely bad | 0.0 | |
| No Alaska county with a monitor matches “”. Counties without a monitor aren't listed; a neighbor's numbers are a fair guide, or find it on the map. | ||
Counties without a monitor aren't listed. Air doesn't stop at the county line, so a neighbor's numbers are a fair guide.
What helps on a bad-air day
Check AirNow for today's reading and tomorrow's forecast, then match the step to the pollutant.
Upgrade the furnace filter
MERV 13 catches far more smoke than thin fiberglass filters.
Furnace filters →Questions people ask about air quality in Alaska
Which county in Alaska has the worst air?
Among Alaska counties with EPA monitors, Fairbanks North Star Borough had the most bad-air days from 2021 to 2025: about 32 bad-air days a year with an AQI over 100. That's about 1 day in 12.
How often is the air bad in Alaska?
Weighted by population, Alaska counties with monitors averaged about 6 bad-air days a year from 2021 to 2025 with an AQI over 100, when children, older adults and people with asthma should cut back outdoors. That's about 1 day in 57.
Which county in Alaska has the cleanest air?
Of the 5 counties with enough monitor data, Denali Borough had the fewest, with no bad-air days at all from 2021 to 2025. Counties without monitors aren't ranked.
Where can I check today's air quality in Alaska?
AirNow, run by the EPA and its partners, shows current readings and forecasts by ZIP code, and its fire and smoke map adds smoke plumes and low-cost sensors.
Sources: EPA AirData county AQI summaries, 2021 to 2025; CDC Environmental Public Health Tracking Network modeled PM2.5 and ozone, 2018 to 2022. Updated November 8, 2026.