Storm drain valves at three locations along the city’s flood protection wall were closed Thursday in preparation for rising water still forecast to reach flood stage in Vicksburg on March 29.

The Mississippi River at Vicksburg stood at 40.1 feet this morning, up three-tenths of a foot since Thursday. It is forecast to crest at 43 feet and become the city’s third official flood in four years.

The drains around City Front are being closed to prevent water from the Yazoo Diversion Canal from seeping under the floodwall and onto streets.

The Ohio River at Cairo, Ill., this morning was cresting at 53.5 feet, 13 feet above flood stage, said Marty Pope, senior service hydrologist with the National Weather Service in Jackson. The crest there is significant because it comes ahead of forecasted rain of about 1 or 2 inches between today and Monday, keeping downriver crest forecasts firm.

“It’s fairly light rainfall,” Pope said.

The Ohio and Mississippi come together at Cairo.

Snow melt from the Midwest has contributed to recent floods on the Lower Mississippi, including the 2008 flood in Vicksburg that crested at 50.9 feet, the highest stage in 35 years.