What is a seiche?
A sieche is when strong storms push water to the other side of the body of water. In this case, it was Lake Michigan. When the storms exited the Lake, the water rushed back in a seiche, or prolonged high wave. Official readings indicated sea levels rose by 18 inches when the seiche came back in.
Why is a seiche dangerous?
Because it is basically a small, prolonged tsunami, if you will. You can become trapped in a suddenly rapidly rising body of water, and thus the potential of drowning rises.
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