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, 06/18/26

Good

For current conditions, see map below.

Cautionary Statements

AQI Forecast

Forecast for Thursday, 06/18/26

Good

For local forecasts, see table below.

Restrictions For Regulated Community

Thursday, 06/18/26

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

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

Local AQI Forecast

Town	Thursday, 06/18/26 FineParticles (PM2.5)	Thursday, 06/18/26 Ozone (O3)
Bridgeport	39	50
Danbury	28	47
Greenwich	39	50
Hartford	33	49
Madison	22	48
Middletown	33	49
New Haven	39	50
New London-Groton	22	46
Stafford	22	44
Stratford	39	50
Torrington	22	44
Waterbury	33	49
Westport	39	50

Receive AQI Notices

DEEP Air Quality Information
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DEEP Ozone Forecast
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EnviroFlash
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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.