A flood warning is in effect in the Pittsburgh region through 4:30 p.m. Thursday, according to the National Weather Service.
The warning applies to Allegheny, Greene, Washington and Westmoreland counties, along with southern Beaver County, southwestern Armstrong County, northern Fayette County and southwestern Indiana County.
Communities expected to experience flooding included Pittsburgh, Mt. Lebanon, Ross, McCandless, Penn Hills, Bethel Park, Monroeville and Moon in Allegheny County; Peters in Washington County; and Greensburg in Westmoreland county.
The weather service predicted up to an inch of rain would fall across the region and flood small streams, poor drainage areas and low-lying spots.