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Air Quality Index

The U. S. Environmental Protection Agency (EPA) has provided a scale called the Air Quality Index (AQI) for rating air quality. This scale is based on the National Ambient Air Quality Standards (NAAQS). The AQI forecast is updated once daily, excluding weekends and holidays. Alternatively, you may call the Air Quality Index Hotline at (800) 249-1234 or (860) 424-4167 for the forecast or link to Airnow.gov for the most current air quality information.

Current air quality is provided below the AQI forecast section.



Current Air Quality

Air Quality for Thursday, 07/09/26

Good to Unhealthy For Sensitive Groups
AQI Scale

For current conditions, see map below.

Cautionary Statements

AQI Forecast

Forecast for Thursday, 07/09/26

Moderate to Unhealthy For Sensitive Groups

Forecast for Friday, 07/10/26

Good to Moderate

For local forecasts, see table below.

Restrictions For Regulated Community

Thursday, 07/09/26

Restrictions Apply

Friday, 07/10/26

Restrictions Do Not Apply

For details, see operating restrictions page.

Historical Ozone Data
Forecasted Ozone Exceedance Days
Tips for Ozone Action Days
Air Monitoring in Connecticut


Local AQI Forecast

Town Thursday, 07/09/26
FineParticles (PM2.5)		 Thursday, 07/09/26
Ozone (O3)		 Friday, 07/10/26
FineParticles (PM2.5)		 Friday, 07/10/26
Ozone (O3)
Bridgeport 56 108 50 71
Danbury 54 101 44 46
Greenwich 56 105 50 54
Hartford 56 90 39 49
Madison 52 108 50 77
Middletown 56 105 39 50
New Haven 54 112 50 58
New London-Groton 52 101 50 80
Stafford 56 80 39 44
Stratford 56 108 50 71
Torrington 52 67 39 43
Waterbury 52 105 44 50
Westport 56 112 50 67

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If you have any questions regarding the Air Quality Forecast, please contact the Bureau of Air Management by phone at (860) 424-4152 or by email.