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 Wednesday, 08/19/26

Good
AQI Scale

For current conditions, see map below.

Cautionary Statements

AQI Forecast

Forecast for Wednesday, 08/19/26

Good to Moderate

Forecast for Thursday, 08/20/26

Moderate

For local forecasts, see table below.

Restrictions For Regulated Community

Wednesday, 08/19/26

Restrictions Do Not Apply

Thursday, 08/20/26

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 Wednesday, 08/19/26
FineParticles (PM2.5)		 Wednesday, 08/19/26
Ozone (O3)		 Thursday, 08/20/26
FineParticles (PM2.5)		 Thursday, 08/20/26
Ozone (O3)
Bridgeport 50 67 58 35
Danbury 44 41 54 34
Greenwich 50 54 58 38
Hartford 39 39 56 33
Madison 50 74 58 32
Middletown 39 46 56 37
New Haven 50 51 56 31
New London-Groton 50 71 58 42
Stafford 33 42 52 32
Stratford 50 67 58 35
Torrington 33 36 52 31
Waterbury 44 46 54 37
Westport 50 67 58 36

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 

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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.