Move workouts to the morning
Ozone peaks on hot, sunny afternoons. Mornings are usually cleaner.
Ozone guide →Includes Fernley · EPA monitor readings, 2021 to 2025 (ozone only) · 59,000 people
For today's air and tomorrow's forecast, check AirNow by ZIP code.
8 bad-air days in 5 years of readings, 2021 to 2025. Lyon County has the 2nd fewest bad-air days of the 9 Nevada counties with monitors.
Average bad-air days in each month, from 10 years of daily readings since 2016. Most fall in July, August and September. Only ozone is measured here.
| Month | Ozone | Fine particles | Dust | All |
|---|---|---|---|---|
| January | 0 | 0 | 0 | 0 |
| February | 0 | 0 | 0 | 0 |
| March | 0 | 0 | 0 | 0 |
| April | 0 | 0 | 0 | 0 |
| May | 0.1 | 0 | 0 | 0.1 |
| June | 0 | 0 | 0 | 0 |
| July | 0.8 | 0 | 0 | 0.8 |
| August | 1.3 | 0 | 0 | 1.3 |
| September | 0 | 0 | 0.6 | 0.6 |
| October | 0 | 0 | 0 | 0 |
| November | 0 | 0 | 0.1 | 0.1 |
| December | 0 | 0 | 0 | 0 |
The worst day since 2016 was September 17, 2020: AQI 328, from dust and coarse particles.
Ozone is the only pollutant measured here. Most bad days counted here are ozone days: smog that builds on hot, sunny afternoons. Monitors here don't measure fine particles, so smoky days aren't in these counts.
CDC's model estimates about 14.4 days a year with high fine particles at the county's worst spot, 2018 to 2022. See the estimates on the map
The CDC's model counts bad-air days at the county's worst spot, from monitors and satellites. Particles (brown) fill the inside of the ring and ozone (blue) the outside.
| Month | Fine particles | Ozone |
|---|---|---|
| January | 0 | 0 |
| February | 0 | 0 |
| March | 0 | 0 |
| April | 0 | 0 |
| May | 0 | 0.2 |
| June | 0.3 | 0.6 |
| July | 0.7 | 0.7 |
| August | 2.0 | 1.1 |
| September | 1.2 | 0.1 |
| October | 0 | 0 |
| November | 0 | 0 |
| December | 0.1 | 0 |
Monitors here track ozone, which builds on hot afternoons, so timing helps. They don't track smoke, so it's worth having a clean room ready too.
Ozone peaks on hot, sunny afternoons. Mornings are usually cleaner.
Ozone guide →AirNow posts an air quality forecast by ZIP code, usually the day before.
AirNow →Shut the windows and run an air purifier sized for the room.
Choosing a purifier →For today's reading and tomorrow's forecast, check AirNow by ZIP code. Its fire and smoke map adds smoke plumes.
For a clean room on smoky days. Each has a smoke CADR tested by AHAM's independent program and is certified by California as a mechanical cleaner, so it makes no ozone.
143 smoke CADR
The cheapest unit we found with a verified smoke rating. Enough for a bedroom clean room.
$119.99 at Levoit250 smoke CADR
The most verified smoke cleaning per dollar of any qualifying model: 75% more than the 100S-P for $50 more.
$169.99 at Levoit391 smoke CADR
For a big room or a small apartment. Buy the LAP-C601S-WUS version, which CARB lists as mechanical.
$299.99 at LevoitWhy all 3 are Levoit: of the models we checked that pass both tests, these give the most verified smoke cleaning per dollar at each room size. Medify's MA-25 and MA-40 also pass but cost more for the same cleaning.
Ratings from the AHAM Verifide directory and CARB's certified list. Prices from Levoit's site, checked November 7, 2026; they change. We don't earn anything from these links. How to pick a purifier
Bad-air days each year. The striped part is days unhealthy for everyone, over AQI 150. The worst recent year was 2021, with 7 bad-air days.
| Year | Bad-air days | Over 150 |
|---|---|---|
| 2012 | 5 | 0 |
| 2013 | 0 | 0 |
| 2014 | 2 | 0 |
| 2015 | 4 | 0 |
| 2016 | 1 | 0 |
| 2017 | 3 | 0 |
| 2018 | 8 | 0 |
| 2019 | 0 | 0 |
| 2020 | 9 | 4 |
| 2021 | 7 | 0 |
| 2022 | 1 | 0 |
| 2023 | 0 | 0 |
| 2024 | 0 | 0 |
| 2025 | 0 | 0 |
Bad-air days a year, 2021 to 2025. Nevada counties with monitors averaged about 25 bad-air days a year, weighted by population.
Nearest county with a full report: Fresno County, CA (65 bad-air days a year).
From 2021 to 2025, monitors in Lyon County recorded about 2 bad-air days a year with an AQI above 100, which is unhealthy for sensitive groups or worse. The worst year in that stretch was 2021, with 7 bad-air days.
Most bad days counted here are ozone days: smog that builds on hot, sunny afternoons. Bad days cluster in July, August and September. Monitors here don't measure fine particles, so smoky days aren't in these counts.
AirNow, run by the EPA and its partners, shows the current AQI and tomorrow's forecast for your ZIP code. Its fire and smoke map adds smoke plumes. On a typical day the AQI in Lyon County is about 41, which is good, fine for everyone. Check it most in July, August and September, when bad days here cluster.
Day counts come from the EPA's county air quality summaries, which take the worst reading across a county's monitors each day. Monitors here reported on about 336 days a year from 2021 to 2025. A county is large, and your street can be cleaner or worse. CDC's model, which estimates every county from monitors and satellites, gives the worst spot in Lyon County about 14 high-particle days and about 5 high-ozone days a year from 2018 to 2022.
Sources: EPA AirData county AQI summaries (2000 to 2025) and daily county AQI (2016 to 2025); CDC Environmental Public Health Tracking Network modeled PM2.5 and ozone (2001 to 2022). Updated November 8, 2026.