Air quality in United States
Air quality in Connecticut today
Updated
Moderate: average US AQI 59 across 10 cities in Connecticut Worst now: Stamford (72); cleanest: Norwich, CT (44).
Live US AQI, PM2.5 and ozone for cities across Connecticut, compared with the United States average.
- Average US AQI
- 59 Moderate
- United States average
- 49 619 cities
- Most polluted now
- Stamford AQI 72
- Cleanest now
- Norwich, CT AQI 44
- Cities above 100
- 0
Air quality in Connecticut today
Right now the modelled air quality in Connecticut averages a US AQI of 59 (Moderate) across the 10 cities we track. By category: 1 Good, 9 Moderate (of 10).
That is 10 points worse than the United States average of 49, ranking 43 of 51 states from cleanest to most polluted.
Stamford has the worst air at 72 (PM2.5 7 µg/m³), and Norwich, CT the cleanest at 44. No tracked city is above 100, so no group needs to change plans.
Connecticut cities by AQI (most polluted first)
| City | US AQI | Category | PM2.5 µg/m³ | PM10 µg/m³ | Ozone µg/m³ |
|---|---|---|---|---|---|
| Stamford | 72 | Moderate | 7 | 7 | 98 |
| Norwalk | 72 | Moderate | 7 | 7 | 98 |
| Hartford | 58 | Moderate | 4.4 | 5 | 86 |
| Bristol | 58 | Moderate | 4.4 | 5 | 86 |
| Windsor | 58 | Moderate | 4.4 | 5 | 86 |
| Farmington | 58 | Moderate | 4.4 | 5 | 86 |
| Bloomfield | 58 | Moderate | 4.4 | 5 | 86 |
| New Haven | 56 | Moderate | 4.4 | 4 | 98 |
| Milford | 56 | Moderate | 4.4 | 4 | 98 |
| Norwich | 44 | Good | 3.9 | 4 | 86 |
What the US AQI numbers mean
| US AQI | Category | What it means |
|---|---|---|
| 0-50 | Good | Air quality is satisfactory and poses little or no risk; a good time for outdoor activity. |
| 51-100 | Moderate | Acceptable for most people. Unusually sensitive people should consider shortening long or heavy exertion outdoors. |
| 101-150 | Unhealthy for Sensitive Groups | People with heart or lung disease, older adults, children and teens should cut back on prolonged or heavy exertion outdoors. |
| 151-200 | Unhealthy | Everyone should reduce prolonged or heavy exertion outdoors; sensitive groups should avoid it and keep windows closed. |
| 201-300 | Very Unhealthy | Health alert: everyone should avoid prolonged or heavy exertion outdoors, and sensitive groups should stay indoors. |
| 301-500 | Hazardous | Emergency conditions: everyone should avoid all outdoor physical activity and stay indoors with filtered air if possible. The scale tops out at 500; heavier dust or smoke is shown as 500. |
Modelled by CAMS (Copernicus) via Open-Meteo, refreshed twice a day; read hour by hour from the forecast.
Cities in Connecticut
- Air quality in Bridgeport
- Air quality in New Haven
- Air quality in Stamford
- Air quality in North Stamford
- Air quality in Hartford
- Air quality in Waterbury
- Air quality in Norwalk
- Air quality in Bristol
- Air quality in Milford
- Air quality in Norwich
- Air quality in Manchester
- Air quality in Windsor
- Air quality in Westport
- Air quality in Farmington
- Air quality in Bloomfield
More
Data: Open-Meteo Air Quality API, Copernicus Atmosphere Monitoring Service (CAMS).