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

Moderate

For current conditions, see map below.

Cautionary Statements

AQI Forecast

Forecast for Friday, 07/17/26

Moderate to Unhealthy For Sensitive Groups

For local forecasts, see table below.

Restrictions For Regulated Community

Friday, 07/17/26

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

For more information, visit the AIRNow Interactive Map of Air Quality website.

Local AQI Forecast

Town	Friday, 07/17/26 FineParticles (PM2.5)	Friday, 07/17/26 Ozone (O3)
Bridgeport	136	44
Danbury	131	34
Greenwich	136	38
Hartford	91	36
Madison	102	44
Middletown	91	37
New Haven	112	38
New London-Groton	102	40
Stafford	86	36
Stratford	136	44
Torrington	86	35
Waterbury	134	37
Westport	136	44

Receive AQI Notices

DEEP Air Quality Information
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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.