Manchester Air Quality in 2020
In 2020, Manchester's air quality (Manchester-Nashua, NH area) had a median daily AQI of 37 (Good) across 366 monitored days. 0 days (0.0%) reached Unhealthy for Sensitive Groups or worse, 351 were Good, and the year's peak AQI was 90 (Moderate). Ground-level ozone set the daily AQI on 337 of those days. The cleanest month of 2020 was November (median AQI 29, 0 days above 100) and the worst was June (median 44, 0 days above 100, peak 74).
- Good: 95.9%
- Moderate: 4.1%
- Unhealthy for Sensitive Groups: 0.0%
- Unhealthy or worse: 0.0%
Reduce Indoor Ozone in Manchester
Today's main pollutant in Manchester is ground-level ozone (AQI 26). Important: standard HEPA filters do NOT remove ozone — only a purifier with a substantial activated-carbon bed adsorbs it. The biggest wins are cutting indoor sources (gas appliances, certain "ionizer" purifiers) and ventilating when outdoor ozone is low (early morning). A high-carbon unit helps with the gases and VOCs that linger indoors.
Recommended: Levoit Core 300 — True HEPA + activated carbon · CADR ~141 CFM · rooms up to 219 sq ft
As an Amazon Associate, we earn from qualifying purchases.
How was Manchester's air quality in 2020?
Good on a typical day: median AQI 37, with 0 days above AQI 100 out of 366 monitored — the 2nd cleanest of 7 years on record for the area.
- ✓Peak AQI in 2020: 90 (Moderate).
- ✓Ground-level ozone was the main pollutant on 337 days.
- ✓Cleanest month: November; worst: June.
Frequently asked questions
What was the average AQI in Manchester in 2020?▾
EPA's Air Quality System puts Manchester's (Manchester-Nashua, NH) median daily AQI for 2020 at 37, which is Good. 0 days were Unhealthy for Sensitive Groups or worse and the year's highest AQI was 90.
Which month had the worst air quality in Manchester in 2020?▾
The cleanest month of 2020 was November (median AQI 29, 0 days above 100) and the worst was June (median 44, 0 days above 100, peak 74).
Was 2020 a good or bad year for Manchester's air?▾
Among the 7 years EPA has published for the area (2019–2025), 2020 ranks 2nd cleanest by days above AQI 100. 2020's median of 37 is in line with the area's typical annual median of 37.
Manchester month by month in 2020
Manchester air quality month by month, 2020 (Manchester-Nashua, NH, EPA AQS daily AQI)
| Month | Days monitored | Median AQI | Days above 100 | Peak AQI | Main pollutant |
|---|---|---|---|---|---|
| January | 31 | 34 | 0 | 44 | O3 |
| February | 29 | 37 | 0 | 52 | O3 |
| March | 31 | 41 | 0 | 49 | O3 |
| April | 30 | 43 | 0 | 51 | O3 |
| May | 31 | 43 | 0 | 51 | O3 |
| Juneworst | 30 | 44 | 0 | 74 | O3 |
| July | 31 | 37 | 0 | 67 | O3 |
| August | 31 | 37 | 0 | 90 | O3 |
| September | 30 | 31 | 0 | 64 | O3 |
| October | 31 | 31 | 0 | 46 | O3 |
| Novembercleanest | 30 | 29 | 0 | 53 | O3 |
| December | 31 | 31 | 0 | 52 | O3 |
How 2020 compares
Among the 7 years EPA has published for the area (2019–2025), 2020 ranks 2nd cleanest by days above AQI 100.
2020's median of 37 is in line with the area's typical annual median of 37.
Activity-specific thresholds: running, cycling, kids' sports.
Right now in Manchester
The latest EPA AirNow observation puts Manchester's AQI at 26 (O3). The figures above are multi-year annual statistics, not today's reading.
View current Manchester air quality →Source: EPA Air Quality System (AQS) pre-generated Daily AQI by CBSA files — daily AQI by CBSA (Manchester-Nashua, NH), 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.