Forecasters at NOAA’s National Weather Service have warned that many rivers in the upper Midwest and northern Plains remain above flood stage, and the threat for more flooding will continue through the summer.
With rivers running high and soils completely saturated, just a small amount of rain could trigger more flooding, including areas that have already seen major to record flooding.
NOAA’s Climate Prediction Center is forecasting above-normal rain in most of these vulnerable areas in the next two weeks, and above-normal rainfall in much of the region in the one- and three-month outlooks.
Adding to the flood threat will be the rising temperatures over the Rockies, which will release the water from the remaining snowpack.
“The sponge is fully saturated – there is nowhere for any additional water to go,” said Jack Hayes, Ph.D., director of NOAA’s National Weather Service. “While unusual for this time of year, all signs point to the flood threat continuing through summer.”
Forecasters say this season could rival the Great Flood of 1993, when the upper Midwest endured persistent, record-breaking floods from April through August, impacting nine states and causing more than $25 billion in damages (adjusted for inflation).
As flood threats continue in these areas, NOAA’s partners at the Federal Emergency Management Agency are continuing to support the response efforts in all of the impacted states. And they continue to urge all residents to take steps now to get ready for severe flooding and other hazards.
Throughout the rest of the summer, the highest flood risk areas include:
– North Central U.S. including Souris River (North Dakota) and Red River of the North (border of North Dakota and Minnesota), Minnesota River (Minnesota), Upper Mississippi River (Minnesota and Iowa), and Des Moines River (Iowa)
– Lower Missouri River from Gavin’s Point (Nebraska and South Dakota border) downstream along the border of Nebraska and Iowa, continuing through the borders of Kansas and Missouri then through Missouri to the Mississippi River
– Tributaries to the Lower Missouri including the James and Big Sioux Rivers in North Dakota
– Lower Ohio River Valley including the White, Wabash and lower Ohio River
– East of Rockies: North Platte River in Colorado, Wyoming and Nebraska and Yellowstone River in Wyoming and Montana
– West of Rockies: Utah and Colorado
Many factors set the stage for this year’s ongoing flood threat, including persistent rainfall last summer and fall, a large winter snowpack across much of the upper Midwest, an unusually cool and wet spring adding additional snowpack in the higher elevations of the Rockies and further saturated soil in lower elevations and in the northern Plains, and above-normal to record river levels for this time of year in the at-risk areas.
source: NOAA press release