Subscribe to receive daily AQI Forecast Notices.

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 Saturday, 07/18/26

Unhealthy For Sensitive Groups to Unhealthy
AQI Scale

For current conditions, see map below.

Cautionary Statements

AQI Forecast

Forecast for Saturday, 07/18/26

Unhealthy For Sensitive Groups to Unhealthy

Forecast for Sunday, 07/19/26

Moderate

For local forecasts, see table below.

Restrictions For Regulated Community

Saturday, 07/18/26

Restrictions Do Not Apply

Sunday, 07/19/26

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 Saturday, 07/18/26
FineParticles (PM2.5)		 Saturday, 07/18/26
Ozone (O3)		 Sunday, 07/19/26
FineParticles (PM2.5)		 Sunday, 07/19/26
Ozone (O3)
Bridgeport 151 50 67 38
Danbury 152 64 69 36
Greenwich 151 64 67 41
Hartford 136 51 71 38
Madison 136 50 67 38
Middletown 136 50 71 39
New Haven 139 50 67 35
New London-Groton 136 50 67 39
Stafford 152 47 69 36
Stratford 151 50 67 38
Torrington 152 61 69 39
Waterbury 151 50 71 39
Westport 151 58 67 39

Receive AQI Notices

  • DEEP Air Quality Information 

    Subscribe to receive a daily ozone forecast between May 1 through September 30, and a daily PM2.5 forecast year round.

  • DEEP Ozone Forecast 

    Subscribe to receive a daily 8-hour ozone forecast for Connecticut's Industrial and Electric Generating Units' combustion sources from May 1 through September 30. test test

  • EnviroFlash 

    Subscribe to receive air quality information by e-mail

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.