Floodwater began to invade the deserted Monongahela Wharf in Downtown Pittsburgh on Friday afternoon, the leading edge of a surge that was expected to add another nine feet to the river by Sunday.

Much of the region, including the city of Pittsburgh, remains under a flood watch through the weekend. The National Weather Service projected that the Mon River would crest at 27.4 feet by 2 p.m. Sunday, 2.4 feet above flood stage.

The wharf floods when the Mon rises to 18 feet. The 10th Street Bypass goes under at 22 feet and the Parkway East next to the wharf is submerged at 25 feet.

The flood of January 1996 produced a crest of 34.6 feet at the Point.

The ultimate severity of the flooding along the Mon, Ohio and Youghiogheny rivers will be determined in part by how much rain falls today. The forecast on Friday wasn't encouraging.

The weather service said rain could be heavy at times today, with 15 to 18 mph winds gusting to 28 mph. More than an inch could fall today and tonight.

"Snow melt has brought rivers to near flood stage. Rain [Friday] and Saturday along with additional snow melt in the mountains is expected to produce flooding," it said.

The weather service has issued flood warnings for the Youghiogheny River at Sutersville, Connellsville and the outskirts of Confluence; and Seward on the Conemaugh River.

Warnings also were issued for French Creek in Meadville, Crawford County; the Cheat River at Rowlesburg, W.Va.; and Coshocton, Ohio, on the Muskingum River.

It said the Monongahela River is expected to crest above flood stage at Braddock, Elizabeth, Charleroi, Maxwell Lock and Dam, Grays Landing and Point Marion between 8 a.m. and 2 p.m. on Sunday. Flood crests are forecast along the Ohio River into West Virginia and Ohio on Monday.

Pittsburgh officials continued their preparations on Friday, filling sandbags at public works sites and spreading leaflets in low-lying areas with advice and evacuation instructions.

Shaler Area High School students fanned out to help residents in Etna and Millvale move their belongings out of harm's way.

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