A ridge of high pressure over the Great Lakes area extending east that has brought the pleasant weather with little wind over the past few days also has created conditions that allow air pollution levels to rise.

The state Department of Environmental Protection has issued an air quality alert from 9 a.m. to 10 p.m. Tuesday for southeastern Allegheny County, which includes the municipalities of Clairton, Glassport, Liberty, Lincoln and Port Vue.

The buildup of pollutants under this stable air mass means residents with respiratory problems should limit outdoor activities.

Check out the PG's weather page for the latest conditions and forecast. Commuters also can access the updated traffic conditions.

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