Slightly above average snowfall in western Wisconsin should still result in a normal flood risk this spring, but it may not help much with relieving drought conditions. Much of the ground in western Wisconsin is experiencing a condition known as concrete frost. The region entered winter with dry soil from the drought, then late rain and snow has created a condition where the topsoil is locked with ice. Mike Welvaert is a hydrologist with the National Weather Service in La Crosse. He says the concrete frost will keep snow from seeping through the ground; were the thaw able to saturate the soil, it would help alleviate drought conditions. "There will be a little bit of a assistance to the top, say, six-seven inches of soil — the top soils — but really, the deep down solid moisture that's really quite dry right now and impacted by the drought conditions all through last summer, that's really not going to be affected by this, because the way the frost is, it's just now going to allow that water to soak down in." Welvaert says drought conditions will also be affected by how rapidly the temperature warms up and melts the snow. "If it melts really quickly and runs off, then it's not going to help our drought any. But if we have a slow, gradual melt and some of that moisture still hangs around here, then maybe it'll have a chance to soak into the soil." Welvaert says the fast melt also means a higher risk of flooding. According the National Weather Service report, there may be minor flooding on the Mississippi River this spring, and its tributary streams and creeks will most likely experience some flooding. With rain and snow predicted this weekend, the threat of flood could increase even more.
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