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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 Friday, 07/17/26

Good to Moderate
AQI Scale

For current conditions, see map below.

Cautionary Statements

AQI Forecast

Forecast for Friday, 07/17/26

Moderate to Unhealthy For Sensitive Groups

Forecast for Saturday, 07/18/26

Unhealthy For Sensitive Groups to Unhealthy

For local forecasts, see table below.

Restrictions For Regulated Community

Friday, 07/17/26

Restrictions Do Not Apply

Saturday, 07/18/26

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 Friday, 07/17/26
FineParticles (PM2.5)		 Friday, 07/17/26
Ozone (O3)		 Saturday, 07/18/26
FineParticles (PM2.5)		 Saturday, 07/18/26
Ozone (O3)
Bridgeport 136 44 151 50
Danbury 131 34 152 64
Greenwich 136 38 151 64
Hartford 91 36 136 51
Madison 102 44 136 50
Middletown 91 37 136 50
New Haven 112 38 139 50
New London-Groton 102 40 136 50
Stafford 86 36 152 47
Stratford 136 44 151 50
Torrington 86 35 152 61
Waterbury 134 37 151 50
Westport 136 44 151 58

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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.