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The seiche at the Soo locks Thursday, Sept. 4, 2014. This navigation lock was in the highest closed position, and water from the seiche was forced over the top of the lock.

(U.S. Army Corps of Engineers - Detroit)

A seiche, which is the Great Lakes version of a tidal wave, hit the eastern shoreline of Lake Superior near Sault Saint Marie around 6 p.m. Thursday, Sept. 4, 2014.

The seiche (pronounced SAYSH) was caused by a dramatic change in wind direction due to severe thunderstorms. The wind was blowing out of the southeast for a long time period, pushing water along the shoreline out into Lake Superior. Then a line of strong thunderstorms moved through, and the accompanying west wind blew the water back into shore.

This is the water level near the Soo locks. The large fluctuation in the middle of the graph shows the seiche and over five feet of water level change.

The U.S. Army Corps of Engineers reported a 65-inch change in water levels. First the water lowered by 14 inches and then quickly rose 51 inches.

Soo Today reported that residents grew concerned as water levels encroached on homes. Water had returned to normal levels within 90 minutes, and residents were urged to test their water before drinking it.

Here is more information on the seiche.

If you have pictures of the seiche, please post them below and email me at mtorregr@mlive.com

MLive Chief Meteorologist Mark Torregrossa has been forecasting Michigan weather for more than 20 years. He's been chief meteorologist at three television news stations in Michigan, and he's an avid gardener and hunter. Email him at mtorregr@mlive.com and find him on Facebook at facebook.com/mark.torregrossa and Twitter @weathermanmark