State environmental officials on Sunday are warning residents about potentially unhealthy air .

The heat wave peaks with apparent temperatures possibly surging into the 100s across the Boston area.

The Massachusetts Department of Environmental Protection has issued an “Air Quality Advisory” across eastern and southeastern counties of the Bay State.

The alert is “due to an expected increase in ozone levels,” MassDEP said in a statement.

“Air in these areas is expected to be unhealthy for sensitive groups,” the environmental agency added.

Sunday is another scorcher of a day across the region.

“The heat peaks today with near record high temperatures of 95 to 100°F,” the National Weather Service’s Boston office tweeted.

Remember to stay cool & hydrated especially if you are heading outdoors.