The National Weather Service has issued a flood advisory for the Ohio and Monongahela rivers at the Point in Downtown Pittsburgh, saying the rivers will crest at 26.5 feet on Sunday afternoon, two feet above flood stage.

In addition, major flooding is expected for the Youghiogheny River, especially the towns of Sutersville and West Newton.

Tonight, the weather service also issued flood warnings for the Yough near Connellsville and Confluence, and the Conemaugh River at Seward affecting Westmoreland and Indiana counties, where it said major flooding is likely.

The high water will be more than enough to flood the Monongahela Wharf, the 10th Street Bypass, the Parkway East "bathtub" adjacent to the wharf and portions of the North Shore riverwalk.

The Pittsburgh Parking Authority announced today that the wharf will be closed Friday and until further notice.

"The combination of snow melt across the region and the expected rainfall that is expected to begin overnight will create significant rises on the Monongahela River" sufficient to flood the wharf by early Friday, the weather service said.

The wharf, which floods at a river stage of 18 feet, will remain underwater until at least Tuesday, the weather service said.

The weather service today also issued flood warnings in several West Virginia counties and four in northern and eastern Ohio. Tonight it added Preston County, W.Va., to the list, saying the Cheat River was expected to flood.

The warning until 7 p.m. Saturday also affected Barbour, Nicholas, Randolph, Upshur, Webster and Pocahontas counties in West Virginia. At 11:30 a.m. emergency management officials reported streams were running high from melting snow. The weather service said the melt will continue with warm temperatures into the weekend, with a chance of showers.

In Ohio, the warning for this afternoon and evening was for Killbuck Creek in Wayne and Holmes counties and the Black River at Elyria, Grand River at Painesville and the Scioto River near LaRue. The counties affected are Lake and Lorain.

The weather service said the rivers at the Point would rise by more than 10 feet between this afternoon and Sunday afternoon.

The Mon also is expected to crest above flood stage at Braddock on Saturday and at Charleroi and Elizabeth Friday evening. Major flooding was forecast along the Youghiogheny River at Sutersville and West Newton late Saturday or early Sunday.

The river level at Sutersville is expected to rise more than 14 feet by Sunday morning.

As waters rise, the Rivers Casino is readying sandbags on the North Shore riverfront outside the venue "purely as a precaution," spokesman Jack Horner said today.

The casino, with 3,000 electronic slot machines, could be heavily damaged if flood waters reach the building, but Mr. Horner said officials, after consulting with the city, are not expecting that.

"All indications are that this water is not coming up that high. But with Mother Nature being somewhat unpredictable, we decided to err on the side of caution," he said.

River stage forecasts and information about the impact of various flood levels is available from the National Weather Service at http://newweb.erh.noaa.gov/ahps2/index.php?wfo=pbz.

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