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Apostle Islands National LakeshoreVisitors on Julian Bay Beach
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Apostle Islands National Lakeshore
Weather
 

Lake Superior is renowned for its cold temperatures, rough seas, fog, and sudden squalls.  Boaters and paddlers should monitor marine weather forecasts and be constantly alert to changing conditions.

Average daytime high temperatures range from 60 degrees Fahrenheit in May, to the upper 80s in mid-summer, to the mid-60s in September. Average lows vary from 40 degrees in May, to the upper 50s in mid-summer, to 50 degrees in September.  Average water temperatures in May and June are only in the 40s.  Even in late summer, surface temperatures rarely exceed 60 degrees, except in protected bays. Average summer winds blow at from 5 to 20 knots with waves of from one to four feet.  Winds of 30 to 40 knots and 6 to 12 foot seas are possible.

Check for an up-to-date weather on Lake Superior

Near Shore Marine Weather Forecast, within 5 miles of shore

Offshore Marine Weather Forecast, beyond 5 miles from shore

Weather Station - Devils Island, WI, located on the Devils Island Lighthouse

West Lake Superior Bouy, located 48 nautical miles North of Ironwood, Michigan

Lake Chart  

Did You Know?
There are actually 22 Apostle Islands (not 12, as might be implied by the name "Apostle"). All but one are included in the national lakeshore.

Last Updated: August 21, 2006 at 17:10 EST