Despite a snowier-than-average winter and historic levels of frost depth, spring flooding isn’t expected to set any records.
In National Weather Service hydrologist Mike Welvaert’s second of two spring flooding outlooks, he cited drier-than-normal soils in portions of the region, along with lighter, fluffier snow contributing to a prediction of normal flooding outlooks for much of the region.
In Winona, there is an even chance of minor flooding along the Mississippi River, with a 21 percent chance of moderate flooding. That’s in comparison to Wabasha, where there’s an 84 percent chance of reaching minor flood stage and 15 percent chance of moderate flood stage. Other cities have variable probabilities of flooding, but are all close to historical averages.
Across the river, areas of western Wisconsin along the Black, Trempealeau and Kickapoo rivers are predicted to have higher-than-average risks of flooding this year, after high levels of precipitation. Despite the increased risk, chances of severe flooding are still relatively low in these areas and across the region.
One concern Welvaert had in the outlook was frost levels.
Due to bitterly cold temperatures this winter, much of southeast Minnesota had frost reach depths of at least three to four feet, with some areas in the region at five feet and deeper. Welvaert said the soil will be able to absorb some water from spring melting, but warmer temperatures or heavy rains could cause flooding due to frozen ground.