Spring rains and melting snow are helping to create the potential for major or moderate flooding in 25 states, with the greatest threat in the northern Plains and the upper Mississippi River basin, said NOAA in a spring outlook issued on Thursday. “The extensive flooding we’ve seen in the past two weeks will continue through May and become more dire, and may be exacerbated in the coming weeks as the water flows downstream,” said director Ed Clark of NOAA’s National Water Center.
“This is shaping up to be a potentially unprecedented flood season, with more than 200 million people at risk for flooding in their communities,” the outlook said. The National Oceanic and Atmospheric Administration said that above-average precipitation is likely in most of the United States this spring, increasing the risk of floods.
Record flooding has already occurred in the upper Mississippi and Missouri river basins, including in Nebraska, Minnesota, and Iowa. Rain and snowfall in the upper Mississippi and Red River of the North basins are as much as 200 percent above normal, said NOAA.
The weather agency said the areas at greatest risk of moderate to major flooding include the upper, middle, and lower Mississippi River basins, including the main stem of the Mississippi River; the Red River of the North; the Great Lakes; the eastern Missouri River basin; and the lower Ohio River, lower Cumberland River, and Tennessee River basins.