Heavy rain is causing flooding on some roadways in the Pittsburgh area.

The intersection of McKnight Road and Siebert Road in Ross Township has been closed due to flooding that has trapped some vehicles, a 911 dispatcher said. People are being directed through the parking lot of an adjacent shopping area.

Two feet of water has flooded Route 18 in Monaca, Beaver County from the 17th Street bridge to Monaca Road, a dispatcher said. The four-lane highway has been closed until the water retreats.

The National Weather Service has issued an advisory for minor flooding of poor drainage areas in Allegheny, Butler, Beaver and Washington counties effective until 11:45 p.m. tonight.

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