Lake Superior water levels could hit record highs this month

Grand Portage Island sits off the Lake Superior shore
Grand Portage Island (top right) is seen off the Lake Superior shore.
Derek Montgomery for MPR News 2016

Abnormally high precipitation and runoff are pushing Lake Superior to what could become record-breaking water levels for the month of May.

Water levels on the great lake increased by more than 5 inches last month, according to the International Lake Superior Board of Control. That's about 62 percent more than the average water level increase for April.

The board said communities along Lake Superior should prepare for shoreline erosion.

"The high levels coupled with potential strong winds and waves are likely to continue to result in an increased risk of shoreline erosion and coastal damages across the upper Great Lakes system," the board wrote in a statement.

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Lake Superior is sitting at about 15 inches higher than historical averages for May, and 9 inches higher than it was this time last year.

Climate change is causing increased precipitation, often in the form of extreme rains, in many parts of the country. The Great Lakes region is experiencing some of the fastest increases in rain and snow totals.

Scientists say Lake Superior levels will likely continue to fluctuate. Despite the high water now, recent studies suggest the long-term effect of climate change may be water loss.

That's because higher temperatures, at times, have resulted in greater water evaporation from the lake.