New Haven Air Quality in November
Across 2019–2025, New Haven's November air quality had a median AQI of 41 (Good) over 210 monitored days in the New Haven-Milford, CT area. 0.0% of November days (0 of 210) reached Unhealthy for Sensitive Groups or worse, and fine particulate matter (PM2.5) set the daily AQI on 70.5% of days. The cleanest November on record here was 2025 (median AQI 36, 0 days above 100) and the worst was 2020 (median 52, 0 days above 100, peak AQI 98).
- Good: 65.7%
- Moderate: 34.3%
- Unhealthy for Sensitive Groups: 0.0%
- Unhealthy or worse: 0.0%
Reduce Indoor Ozone in New Haven
Today's main pollutant in New Haven is ground-level ozone (AQI 32). 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 is the air in New Haven in November?
Good on a typical day: median AQI 41 across 2019–2025, with 0.0% of November days above AQI 100. Fine particulate matter (PM2.5) is the main driver.
- ✓65.7% of November days were Good (AQI 0–50), 34.3% Moderate (51–100).
- ✓0 days of 210 reached AQI 101+; the November peak was 98.
- ✓Best November: 2025; worst November: 2020.
Frequently asked questions
What is the air quality like in New Haven in November?▾
Across 2019–2025, the median daily AQI in New Haven in November was 41 (Good). 65.7% of days were Good, 34.3% Moderate, and 0.0% reached Unhealthy for Sensitive Groups or worse, based on 210 monitored days in EPA's Air Quality System.
Is November a good time for outdoor exercise in New Haven?▾
A typical November day in New Haven sits in the Good range (median AQI 41), so running, cycling and children's outdoor play are fine for everyone on most days; fewer than 1% of November days reached AQI 101+ in 2019–2025.
Which pollutant causes New Haven's November air quality problems?▾
Fine particulate matter (PM2.5) set the daily AQI on 70.5% of November days in New Haven. The highest November AQI recorded in 2019–2025 was 98 (Moderate), in 2020.
New Haven November air quality, year by year
New Haven November air quality by year (New Haven-Milford, CT, EPA AQS daily AQI)
| Year | Days monitored | Median AQI | Days above 100 | Peak AQI | Main pollutant |
|---|---|---|---|---|---|
| 2019 | 30 | 42 | 0 | 73 | PM2.5 |
| 2020worst | 30 | 52 | 0 | 98 | PM2.5 |
| 2021 | 30 | 43 | 0 | 70 | PM2.5 |
| 2022 | 30 | 46 | 0 | 64 | PM2.5 |
| 2023 | 30 | 43 | 0 | 66 | PM2.5 |
| 2024 | 30 | 37 | 0 | 54 | O3 |
| 2025cleanest | 30 | 36 | 0 | 75 | PM2.5 |
What November air means in New Haven
A typical November day in New Haven sits in the Good range (median AQI 41), so running, cycling and children's outdoor play are fine for everyone on most days; fewer than 1% of November days reached AQI 101+ in 2019–2025.
November's median AQI of 41 is in line with New Haven's whole-year median of 44, so this period is neither a clean nor a dirty stretch for the area. Nationally, the median November AQI across every EPA metro area (92,704 metro-days, 2019–2025) is 39, so New Haven runs in line with the national November norm; 0.0% of its November days topped AQI 100 versus 0.6% nationally (about the same).
November is part of New Haven's fall season (September, October, November); the fall page pools all three months.
Activity-specific thresholds: running, cycling, kids' sports.
Right now in New Haven
The latest EPA AirNow observation puts New Haven's AQI at 32 (O3). The figures above are multi-year month statistics, not today's reading.
View current New Haven air quality →Source: EPA Air Quality System (AQS) pre-generated Daily AQI by CBSA files — daily AQI by CBSA (New Haven-Milford, CT), 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.