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Lake Superior on verge of record high July water level

Aug 02, 2017 08:47AM ● By Editor

Lake Superior July average water level back to 1940. (Graphic created by Milton Klingensmith | MLive)

By Mark Torregrossa - [email protected]

The Lake Superior water level continues its fourth year of rising. As the water level rises on Lake Superior, it comes closer to the monthly record water level. In July 2017, Lake Superior fell just short of its July record high water level.

In July 2017 the Lake Superior average was 602.85 feet. This number doesn't represent a water depth. It is a height measurement that is used to compare to water levels in other months and other years. It would be similar to if you put some markings on the side of your bathtub. 

The highest water level in July on Lake Superior was 603.08 feet in 1950. Doing the math for you, in July 2017 Lake Superior was .23 of a foot below the record July level, which is 2.76 inches.

The world's largest freshwater lake, ranked by surface area, is just under three inches from its highest July water level.

Water level records for Lake Superior go back to 1860.

With the continued rise of water on Lake Superior, the lake is now 35 inches higher than a recent low water period ending in April 2013. If you look at the graph you see the faster water level rise in the history of Lake Superior water levels.

One inch of water on Lake Superior is equal to 550 billion gallons of water. Looking at it that way, Lake Superior still needed 1.5 trillion extra gallons of water to break the record water level.

Will it actually rain a decent amount in Michigan this week

The storm system late this week is expected to produce widespread heavy rain over the Upper Peninsula and over Lake Superior. It's amazing to know if one inch of rain falls over Lake Superior, it will add 550 billion gallons of water.

The typical high water time for Lake Superior is July. A seasonal fall in water levels usually begins in August. If the much above normal rain keeps falling, Lake Superior will continue to rise instead of go into its seasonal decline. Lake Superior would then be flirting with its all-time high water level.


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