Onalaska, Wisconsin Air Quality
Onalaska has a median AQI of 40, earning an air quality grade of A — excellent air quality that ranks better than 60% of US cities. Air quality has remained relatively stable over the past decade. Ground-level ozone is the primary concern, typically peaking on warm sunny days due to vehicle and industrial emissions. In 2025, Onalaska recorded 81 good air quality days (88% of monitored days).
Population: 19,348 • County: La Crosse
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Quick Facts
| Current AQI | 15 — Good |
| Air Quality Grade | A |
| Median AQI (2025) | 40 |
| vs. U.S. Cities | Better than 60% |
| Primary Pollutant | Ozone |
| Unhealthy Days/Year | 0 |
| 10-Year Trend | → Stable |
| Data Source | EPA AirNow |
Health Recommendation
Air quality is satisfactory, and air pollution poses little or no risk.
It's a great day to be active outside!
5-Day AQI Forecast
Last 30 Days
Current Pollutant Levels
Real-time data from EPA AirNow
AQI Trend (10 Years)
Air Quality Days by Year
2025 Air Quality Summary
Primary Pollutant Days (2025)
Days when each pollutant was the primary driver of AQI. Learn about pollutants →
Frequently Asked Questions About Onalaska Air Quality
What is the air quality in Onalaska today?
The current AQI in Onalaska is 15, which is rated "Good". Air quality is satisfactory, and air pollution poses little or no risk.
Is air quality in Onalaska getting better or worse?
Air quality in Onalaska has remained relatively stable over the past decade, with a median AQI of around 40.
What is the most common air pollutant in Onalaska?
Ozone is the primary air pollutant in Onalaska, responsible for the most air quality-impacted days in 2025. Ground-level ozone forms when sunlight reacts with vehicle and industrial emissions on warm days.
How many unhealthy air days does Onalaska have per year?
In 2025, Onalaska had 0 days when air quality was unhealthy or unhealthy for sensitive groups (AQI above 100). There were 81 good days and 11 moderate days out of 92 days monitored.
What air quality grade does Onalaska receive?
Onalaska receives an air quality grade of A, placing it better than 60% of US cities. This grade is based on a median AQI of 40 for 2025, derived from EPA monitoring data.
Air Quality Grade
Better than 60% of US cities
Nearby Cities
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National Rankings
See how Onalaska compares to every other US city by air quality.
Best Air Quality Cities →All city rankingsRecommended Air Purifiers for Onalaska
Based on your area's air quality (median AQI: 40), we recommend these air purifiers to help protect your health indoors.
RabbitAir MinusA2
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Other Great Options
Molekule Air Pro
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Blueair Blue Pure 211+
High performance for large rooms with simple operation.
Dyson Pure Cool TP04
Premium all-in-one air purifier and fan with advanced features.
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