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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 Friday, 04/17/26

Good to Moderate
AQI Scale

For current conditions, see map below.

Cautionary Statements

AQI Forecast

Forecast for Friday, 04/17/26

Good

Forecast for Saturday, 04/18/26

Good

For local forecasts, see table below.

Restrictions For Regulated Community

Ozone forecasting has come to a close. Ozone concentrations from October through April are expected to remain in the GOOD, to occasionally MODERATE range.

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 Friday, 04/17/26
FineParticles (PM2.5)		 Friday, 04/17/26
Ozone (O3)		 Saturday, 04/18/26
FineParticles (PM2.5)		 Saturday, 04/18/26
Ozone (O3)
Bridgeport 28 44
Danbury 28 44
Greenwich 28 44
Hartford 33 39
Madison 39 33
Middletown 33 39
New Haven 28 39
New London-Groton 39 33
Stafford 22 39
Stratford 28 44
Torrington 22 39
Waterbury 33 44
Westport 28 44
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.