Madison Air Quality in 2025
In 2025, Madison's air quality (Madison, WI area) had a median daily AQI of 42 (Good) across 365 monitored days. 7 days (1.9%) reached Unhealthy for Sensitive Groups or worse, 242 were Good, and the year's peak AQI was 170 (Unhealthy). Fine particulate matter (PM2.5) set the daily AQI on 252 of those days. The cleanest month of 2025 was November (median AQI 31, 0 days above 100) and the worst was August (median 39, 3 days above 100, peak 112).
- Good: 66.3%
- Moderate: 31.8%
- Unhealthy for Sensitive Groups: 1.6%
- Unhealthy or worse: 0.3%
Improve Indoor Air Quality
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How was Madison's air quality in 2025?
Good on a typical day: median AQI 42, with 7 days above AQI 100 out of 365 monitored — the 6th cleanest of 7 years on record for the area.
- ✓Peak AQI in 2025: 170 (Unhealthy).
- ✓Fine particulate matter (PM2.5) was the main pollutant on 252 days.
- ✓Cleanest month: November; worst: August.
Frequently asked questions
What was the average AQI in Madison in 2025?▾
EPA's Air Quality System puts Madison's (Madison, WI) median daily AQI for 2025 at 42, which is Good. 7 days were Unhealthy for Sensitive Groups or worse and the year's highest AQI was 170.
Which month had the worst air quality in Madison in 2025?▾
The cleanest month of 2025 was November (median AQI 31, 0 days above 100) and the worst was August (median 39, 3 days above 100, peak 112).
Was 2025 a good or bad year for Madison's air?▾
Among the 7 years EPA has published for the area (2019–2025), 2025 ranks 6th cleanest by days above AQI 100. 2025's median of 42 is below the area's typical annual median of 45.
Madison month by month in 2025
Madison air quality month by month, 2025 (Madison, WI, EPA AQS daily AQI)
| Month | Days monitored | Median AQI | Days above 100 | Peak AQI | Main pollutant |
|---|---|---|---|---|---|
| January | 31 | 32 | 0 | 66 | PM2.5 |
| February | 28 | 40 | 0 | 71 | PM2.5 |
| March | 31 | 32 | 0 | 80 | PM2.5 |
| April | 30 | 44 | 0 | 63 | O3 |
| May | 31 | 42 | 0 | 87 | O3 |
| June | 30 | 54 | 2 | 136 | PM2.5 |
| July | 31 | 56 | 2 | 170 | PM2.5 |
| Augustworst | 31 | 39 | 3 | 112 | PM2.5 |
| September | 30 | 47 | 0 | 97 | O3 |
| October | 31 | 33 | 0 | 80 | PM2.5 |
| Novembercleanest | 30 | 31 | 0 | 64 | PM2.5 |
| December | 31 | 43 | 0 | 60 | PM2.5 |
How 2025 compares
Among the 7 years EPA has published for the area (2019–2025), 2025 ranks 6th cleanest by days above AQI 100.
2025's median of 42 is below the area's typical annual median of 45.
Activity-specific thresholds: running, cycling, kids' sports.
Right now in Madison
The latest EPA AirNow observation puts Madison's AQI at 49 (PM2.5). The figures above are multi-year annual statistics, not today's reading.
View current Madison air quality →Source: EPA Air Quality System (AQS) pre-generated Daily AQI by CBSA files — daily AQI by CBSA (Madison, WI), 2019–2025. Daily AQI per CBSA is the highest AQI reported by any monitor in the area that day; the defining parameter is the pollutant that set it. Month and season statistics pool every such day in the period across all years listed. Retrieved 2026-09-09.