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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 Thursday, 06/04/26

Good to Moderate
AQI Scale

For current conditions, see map below.

Cautionary Statements

AQI Forecast

Forecast for Thursday, 06/04/26

Good to Moderate

Forecast for Friday, 06/05/26

Moderate to Unhealthy For Sensitive Groups

For local forecasts, see table below.

Restrictions For Regulated Community

Thursday, 06/04/26

Restrictions Apply

Friday, 06/05/26

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 Thursday, 06/04/26
FineParticles (PM2.5)		 Thursday, 06/04/26
Ozone (O3)		 Friday, 06/05/26
FineParticles (PM2.5)		 Friday, 06/05/26
Ozone (O3)
Bridgeport 50 77 52 108
Danbury 39 44 56 54
Greenwich 50 58 52 101
Hartford 39 42 58 58
Madison 44 100 52 108
Middletown 39 50 58 77
New Haven 44 51 52 101
New London-Groton 44 100 52 112
Stafford 28 47 54 64
Stratford 50 77 52 108
Torrington 28 36 54 58
Waterbury 39 50 56 77
Westport 50 80 52 105

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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.