The agency has issued an air quality alert for Friday because ground-level ozone is expected to reach unhealthy levels.

The alert applies from Kittery, Maine, to Acadia National Park.

The National Weather Service says the air quality alert accompanies a shift in the weather pattern, with hot and humid air coming in from the south.

The DEP urges individuals with respiratory disease to avoid the heat and strenuous activities. The alert could continue into Saturday.