It's pretty darn cold. How cold is it? Lake Erie is a pretty much a continuous sheet of ice, NOAA reports, with about 95 percent of the surface covered at 5:15 p.m on Thursday. It's on the threshold of the magical 100 percent frozen mark, which has been achieved only three times in the past 40 years of weather history - in 1977, 1978 and most recently in 1996.
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Hopefully, this won't lead to a lot of people trying to make like Ice Age immigrants and walk across Lake Erie from Cleveland to Canada, as Dave Voelker did back in 1978, another time that the lake froze over completely.
As Voelker explained in a 2007 article, at the narrowest point, the lake is 30 miles across, which requires about two days of hiking. That meant camping out on the ice and enduring nighttime temperatures of 9 degrees F.
During the walk itself, he battled the numbing effects of cold and, paradoxically sun exposure that gave him a nasty facial sunburn, and nearly got lost more than once. He also lost radio contact with people on land. As Voelker, an experienced outdoors adventurer, warns in the article, "To a novice, a winter walk across frozen Lake Erie to Canada is almost certain death."
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A greater portion of Lake Erie is frozen over than the other Great Lakes. Lakes Superior and Huron were close, with upwards of 90 percent, while Ontario and Michigan were about 55 percent covered, according to NOAA. The overall coverage on the Great Lakes was more than 85 percent.
Lake Erie usually usually gets the most surface ice coverage because at an average depth of 62 feet, the lake is relatively shallow, George Leshkevich, a physical scientist for the Great Lakes Environmental Research Laboratory, told USA Today. That means that it can't store as much heat. Lake Ontario, in contrast, averages 282 feet in depth.