The hot, muggy weather this week will stick around until this evening, when thunderstorms are expected to move in and clear the air.

That means an air quality alert is still in effect for the southwest coast from Kittery to Bath and interior regions of southern Maine up to 30 miles inland, according to the Maine Department of Environmental Protection.

Unhealthy levels of ozone and particle pollution remain today for sensitive groups, including individuals suffering from a respiratory disease, said Tom Downs, with the state DEP. However, all residents should take precautions, which includes avoiding strenuous activity outdoors during the mid-day and use of aerosol products such as cleaners and paints.

Early this afternoon, temperatures had reached 84 degrees in Portland and 88 degrees in Sanford.