Flood-prone areas of Minnesota and throughout the Upper Midwest could be in for record flooding this spring after 2019 proved to be the wettest year on record for many locations.
The ominous report comes from the National Weather Service's spring flood outlook.
"Well above normal rain and snowfall throughout 2019 has led to record flooding, record high river levels, and abnormally wet ground for the winter season across the region. Through the end of December 2019, the Upper Mississippi River Basin and Red River Basin have had their wettest year in 125 years of modern record keeping.
"Across the region, Michigan, Minnesota, the Dakotas, Wisconsin and Illinois all recorded their top 5 wettest years (January 2019 – December 2019)."
Soil throughout Minnesota is already holding more moisture than normal for this time of year. That, coupled with already high river levels and what could be a wetter than normal next couple months, could lead to widespread major flooding, ice jams and other flooding concerns.
According to the Star Tribune, the U.S. Army Corps of Engineers has already alerted cities along the Mississippi River from Winona to Guttenberg, Iowa, to prepare for flooding in the possibility of flooding. The report notes that the Mississippi River in southern Minnesota is already moving at three times its normal strength.
The U.S. Army Corps of Engineers has told cities along the river from Winona, Minn., to Guttenberg, Iowa, to monitor and brace for potential flooding in the weeks and months ahead, an unusual concern for late January.
In addition to the precipitation yet to fall, snowpack in Minnesota is currently holding anywhere from 2-8 inches of water. Once the snow melts, that water will only add to the rising river levels, thus exacerbating flooding concerns.
"As of January 22, there is between 10-25 inches of snow depth across portions of North and South Dakota and into northern Minnesota and northern Wisconsin. Isolated snow depth of 30 inches or higher have also been observed in northern Minnesota. This snow is holding anywhere from 2-8 inches of water within it - waiting to be released. The highest amounts can be found from eastern North Dakota to the arrowhead of Minnesota and Upper Peninsula of Michigan."
More from the weather service on why a wetter than normal February-April and other factors could enhance flooding risks.
"The latest 2020 Winter Outlook suggests that odds favor a normal to wetter than normal February through April across much of the Upper Mississippi River and Red River basins, with higher odds farther north. We are also expecting cooler than normal temperatures as you head farther north, which could hold onto the snowpack longer into the spring. This increases the risk for a sudden and high-impact thaw in the spring."
The best-case scenario for preventing major flooding is a prolonged period of dry, warm weather, no extreme cold snaps, and gradual warming to transition from winter to spring.
Worst-case scenarios would be maintaining higher than normal snowpack, a long-lived blast of frigid air that freezes soil beneath bare ground, a quick transition from winter to spring that leads to rapid snow melt, and significant rain on top of snow that forces the water held in the snow faster than normal.