St. Paul Air Quality in 2020
In 2020, St. Paul's air quality (Minneapolis-St. Paul-Bloomington, MN-WI area) had a median daily AQI of 50 (Good) across 366 monitored days. 3 days (0.8%) reached Unhealthy for Sensitive Groups or worse, 186 were Good, and the year's peak AQI was 163 (Unhealthy). Fine particulate matter (PM2.5) set the daily AQI on 250 of those days. The cleanest month of 2020 was September (median AQI 41, 0 days above 100) and the worst was July (median 44, 3 days above 100, peak 163).
- Good: 50.8%
- Moderate: 48.4%
- Unhealthy for Sensitive Groups: 0.5%
- Unhealthy or worse: 0.3%
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How was St. Paul's air quality in 2020?
Good on a typical day: median AQI 50, with 3 days above AQI 100 out of 366 monitored — the 3rd cleanest of 7 years on record for the area.
- ✓Peak AQI in 2020: 163 (Unhealthy).
- ✓Fine particulate matter (PM2.5) was the main pollutant on 250 days.
- ✓Cleanest month: September; worst: July.
Frequently asked questions
What was the average AQI in St. Paul in 2020?▾
EPA's Air Quality System puts St. Paul's (Minneapolis-St. Paul-Bloomington, MN-WI) median daily AQI for 2020 at 50, which is Good. 3 days were Unhealthy for Sensitive Groups or worse and the year's highest AQI was 163.
Which month had the worst air quality in St. Paul in 2020?▾
The cleanest month of 2020 was September (median AQI 41, 0 days above 100) and the worst was July (median 44, 3 days above 100, peak 163).
Was 2020 a good or bad year for St. Paul's air?▾
Among the 7 years EPA has published for the area (2019–2025), 2020 ranks 3rd cleanest by days above AQI 100. 2020's median of 50 is in line with the area's typical annual median of 50.
St. Paul month by month in 2020
St. Paul air quality month by month, 2020 (Minneapolis-St. Paul-Bloomington, MN-WI, EPA AQS daily AQI)
| Month | Days monitored | Median AQI | Days above 100 | Peak AQI | Main pollutant |
|---|---|---|---|---|---|
| January | 31 | 56 | 0 | 80 | PM2.5 |
| February | 29 | 55 | 0 | 68 | PM2.5 |
| March | 31 | 46 | 0 | 66 | PM2.5 |
| April | 30 | 47 | 0 | 68 | PM2.5 |
| May | 31 | 48 | 0 | 60 | O3 |
| June | 30 | 53 | 0 | 87 | PM2.5 |
| Julyworst | 31 | 44 | 3 | 163 | PM2.5 |
| August | 31 | 51 | 0 | 77 | PM2.5 |
| Septembercleanest | 30 | 41 | 0 | 69 | PM2.5 |
| October | 31 | 43 | 0 | 66 | PM2.5 |
| November | 30 | 48 | 0 | 80 | PM2.5 |
| December | 31 | 55 | 0 | 88 | PM2.5 |
How 2020 compares
Among the 7 years EPA has published for the area (2019–2025), 2020 ranks 3rd cleanest by days above AQI 100.
2020's median of 50 is in line with the area's typical annual median of 50.
Activity-specific thresholds: running, cycling, kids' sports.
Right now in St. Paul
The latest EPA AirNow observation puts St. Paul's AQI at 31 (PM2.5). The figures above are multi-year annual statistics, not today's reading.
View current St. Paul air quality →Source: EPA Air Quality System (AQS) pre-generated Daily AQI by CBSA files — daily AQI by CBSA (Minneapolis-St. Paul-Bloomington, MN-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.