Unhealthy Air Forecasted for Thursday

The state’s Department of Environmental Protection is forecasting unhealthy air quality again today for Middlesex, Fairfield, New Haven and New London counties.

The DEP has issued an air quality forecast of “Unhealthy for Sensitive Groups” (Code Orange) because of high concentrations of ground-level ozone predicted for tomorrow. The DEP monitors air quality in the state and the levels can be viewed here.

By Friday, air quality is expected to improve after a cold front, which is expected to move through the state tomorrow night, ushers in a dry, clean air mass from Canada.

A high pressure system centered off the southeastern United States will continue to provide plenty of sunshine over the state for the next day or so, though it is bringing with it hot temperatures. Some weather forecasters are predicting temperatures up near 100 degrees on Thursday.

This combination of heat and southwest winds produces ideal conditions for ozone formation and pushes elevated levels of ozone into the state, DEP officials said. These conditions will persist until Thursday night when an approaching cold front will trigger late-day thunderstorms and cooler air, reducing ground-level ozone by Friday, the DEP said in a press release today.

Anyone can be affected by ozone, but groups particularly sensitive include children and adults who are active outdoors, and people with respiratory diseases, such as asthma. Sensitive people who experience effects at lower ozone concentrations are likely to experience more serious effects at higher concentrations.

The hot weather has prompted East Haddam to open a “cooling center” to residents. Officials in East Haddam today announced the town’s Senior Center would be open daily for those seeking relief from the high temperatures.