The alert is in effect from 1 to 9 p.m. Wednesday for all of coastal Connecticut and all of the eastern side of the Nutmeg State, according to the state Department of Energy and Environmental Protection.
An Air Quality Action Day means that ozone in the region may approach or exceed healthy standards.
Ozone is a colorless gas that is a major constituent of smog. It can irritate the lungs and breathing passages, causing coughing and pain in the chest and throat. It also increases susceptibility to respiratory infections and reduces the ability to exercise.
The effects are more severe in children, the elderly and people with asthma and other respiratory ailments.
The forecast for Wednesday is for sunny skies, with a high in the upper 80s to near 90. There is a chance of showers and thunderstorms before midnight.
For additional information, visit the DEEP website here.
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