Thousands of Minot residents face a Wednesday deadline to evacuate their homes for a second time this spring as the rising Souris River moves closer to swamping the North Dakota city with what’s predicted to be its worst flood in four decades. Officials have ordered about 11,000 people, or a quarter of the city’s residents, to evacuate by 6 p.m. But they cautioned even that deadline may be too generous, and said they are prepared to sound warning sirens if water spills over Minot’s protective levees any earlier.