Air quality in Nevada, county by county

9 Nevada counties have enough EPA monitor data to count bad-air days. Weighted by population, they averaged about 25 days a year from 2021 to 2025 when the air was unhealthy for sensitive groups or worse.

CDC's model, which estimates every county from monitors and satellites, gives the average Nevada county, weighted by population, about 5 smoky days (fine particles over 35.4 µg/m³, mostly wildfire smoke) and about 12 high-ozone days a year at its worst spot (2018 to 2022). See every county on the map.

Every Nevada county with monitors

Most bad-air days first. 6 have a full report. Compare with the worst and the cleanest counties in the US.

CountyBad-air days a yearMain cause
Clark CountyLas VegasOzone 30.4 Ozone
Washoe CountyRenoOzone and particles 10.0 Ozone and particles
Carson CitySummer smoke 7.8 Summer smoke
Douglas CountyGardnerville RanchosSmokeozone not measured 7.8 Smokeozone not measured
Nye CountyPahrumpDust 4.6 Dust
Elko CountyElkoOzone and particles 3.0 Ozone and particles
Churchill CountyFallonOzoneparticles not measured 2.2 Ozoneparticles not measured
Lyon CountyFernleyOzoneparticles not measured 1.6 Ozoneparticles not measured
White Pine CountyOzone 1.4 Ozone

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.

Ozone: exercise in the morning

Ozone peaks on hot, sunny afternoons.

Ozone guide →

Upgrade the furnace filter

MERV 13 catches far more smoke than thin fiberglass filters.

Furnace filters →

Questions people ask about air quality in Nevada

Which county in Nevada has the worst air?

Among Nevada counties with EPA monitors, Clark County had the most bad-air days from 2021 to 2025: about 30 bad-air days a year with an AQI over 100. That's about 1 day in 12.

How often is the air bad in Nevada?

Weighted by population, Nevada counties with monitors averaged about 25 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 15.

Which county in Nevada has the cleanest air?

Of the 9 counties with enough monitor data, White Pine County had the fewest: 1.4 a year from 2021 to 2025. Counties without monitors aren't ranked.

Where can I check today's air quality in Nevada?

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.