The high-pressure system that has brought days of sunny skies to Western Pennsylvania also means air pollution levels are on the rise.

The state Department of Environmental Protection has issued an air quality alert for Allegheny, Armstrong, Beaver, Butler, Fayette, Washington and Westmoreland counties until midnight.

High pressure will keep winds at a minimum, which will allow pollution levels to rise. Residents should limit outdoor activities during the day.

Check out the PG's weather page for the latest conditions and forecast.

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