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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 Saturday, 04/18/26

Good
AQI Scale

For current conditions, see map below.

Cautionary Statements

AQI Forecast

Forecast for Saturday, 04/18/26

Good

Forecast for Sunday, 04/19/26

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 Saturday, 04/18/26
FineParticles (PM2.5)		 Saturday, 04/18/26
Ozone (O3)		 Sunday, 04/19/26
FineParticles (PM2.5)		 Sunday, 04/19/26
Ozone (O3)
Bridgeport 44 33
Danbury 44 33
Greenwich 44 33
Hartford 39 33
Madison 33 28
Middletown 39 33
New Haven 39 28
New London-Groton 33 28
Stafford 39 28
Stratford 44 33
Torrington 39 28
Waterbury 44 33
Westport 44 33
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.