Stay updated with real-time air quality in Stonington, Connecticut featuring accurate data on AQI, PM2.5, PM10, O3, NO2, SO2, and CO levels. Use our interactive map and detailed forecasts to monitor pollution trends, manage health risks, and plan your daily activities with confidence.
Live AQI (Air Quality Index)
27
Good
Stonington, Connecticut
Last updated: ... (Local time)

Good
Fine
Moderate
Poor
Very poor
Hazardous
4.43 μg/m³
0
12.1
35.5
55.5
250.5
500.5+
15.35 μg/m³
0
55
155
255
425
605+
29.02 ppb
0
55
71
86
201
201+
0.18 ppb
0
36
76
186
605
1005+
6.27 ppb
0
54
101
361
1250
2050+
0.21 ppm
0
4.5
9.5
12.5
230.5
50.5+
Pollen Level
Low
Stonington, Connecticut
Stonington, Connecticut
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AQI 27
Good
4.82μg/m³
PM2.5
13.03μg/m³
PM10
29.37ppb
O3
0.18ppb
SO2
5.26ppb
NO2
0.21ppm
CO
AQI 33
Good
5.70μg/m³
PM2.5
11.02μg/m³
PM10
27.99ppb
O3
0.18ppb
SO2
5.20ppb
NO2
0.21ppm
CO
AQI 27
Good
5.18μg/m³
PM2.5
11.38μg/m³
PM10
27.48ppb
O3
0.21ppb
SO2
5.05ppb
NO2
0.21ppm
CO
AQI 33
Good
5.70μg/m³
PM2.5
11.02μg/m³
PM10
27.99ppb
O3
0.18ppb
SO2
5.20ppb
NO2
0.21ppm
CO
AQI 33
Good
5.67μg/m³
PM2.5
11.24μg/m³
PM10
27.93ppb
O3
0.18ppb
SO2
5.17ppb
NO2
0.21ppm
CO
AQI 33
Good
5.58μg/m³
PM2.5
11.62μg/m³
PM10
27.68ppb
O3
0.19ppb
SO2
5.08ppb
NO2
0.21ppm
CO
Air quality and pollutant data for Connecticut, USA are sourced from ground-based monitors and satellites, adhering to US EPA standards. Machine learning and advanced algorithms enhance the data by incorporating local variables like traffic and population density, ensuring high accuracy and dependability.
Source: Ambee Data Sources
The air quality information for Stonington, Connecticut is updated every hour for accuracy.
In the past 24 hours, the air quality in Stonington, Connecticut was at its worst at 05:00:00 on 2026-08-14.
In the last 24 hours, the best air quality in Stonington, Connecticut was observed at 05:00:00 on 2026-08-14.
As of now, the AQI in Stonington, Connecticut is 27, indicating Good conditions.
Stonington, Connecticut air has the highest levels of O3.
Poor air quality in Stonington, Connecticut means it's advisable to stay indoors and wear a mask for your protection.
PM2.5 levels in Stonington, Connecticut are currently 4.427 μg/m3.
The PM10 concentration in Stonington, Connecticut is 15.349 μg/m3 at the moment.
The current carbon monoxide (CO) concentration in Stonington, Connecticut is 0.209 ppm.
Currently, Stonington, Connecticut has a sulfur dioxide (SO2) concentration of 0.177 ppb.
The current ozone (O3) level in Stonington, Connecticut at the moment is 29.023 ppm.
Nitrogen dioxide (NO2) level in Stonington, Connecticut at the moment is 6.267 ppb.
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