Researchers said Lake Superior had the highest ice coverage this season, and ice coverage on the Great Lakes remained above 50% during the season.
As of Monday, March 2, 50.19% of the Great Lakes were covered in ice, according to the Great Lakes Environmental Research Laboratory, a program of the National Oceanic and Atmospheric Administration.
Lake Superior is 55.98% ice-free, its highest percentage for the 2025-26 season and, as of March 1, above-average ice this season compared to historical averages, according to NOAA.
In addition to its impressive coverage, Lake Superior’s ice cap has also grown quite thick. In the lake’s northwest, more than 2 feet of ice has formed along the shores of Black Bay and Nipigon Bay near Thunder Bay, Ontario.
Most of Lake Michigan is ice-free except for northern areas, including Green Bay and the Straits of Mackinac. Much of Lake Erie is frozen over, while Lake Huron is heavily frozen. Lake Ontario is mostly open water.
Michigan is expected to see warmer temperatures across the state, including highs as high as 60 degrees in southern Michigan, so snow and ice coverage may be reduced this week, according to the National Weather Service.
Peak ice season is from mid-February to late February for the lower lakes and from late February to early March for the upper lakes, according to GLERL.
Ice levels in the Great Lakes are near normal in 2024, rebounding from historic winter lows in 2023-24. Lake Erie recorded the highest coverage at 95.8% in 2024-25 (which is typical since it is the shallowest of the Great Lakes), and Lake Superior had the second-highest coverage at its peak at 71.1%.
As the 2025-26 ice season continues, researchers will track the percentage of ice on a daily basis. To track progress, the National Ice Center releases ice maps every Tuesday and Wednesday.
Here’s how much ice is in each of the Great Lakes:
How much ice is there in the Great Lakes today?
Ice thickness on the Great Lakes as of March 1.
Ice cover in the Great Lakes hovered around 50% as of March 1-2, according to the GLERL program and the National Snow and Ice Center.
The Straits of Mackinac, where Lakes Erie and Huron meet Lake Michigan, has formed 2 feet of ice. Thick ice has also expanded along the shores of Lake Huron in Ontario, Canada; Saginaw Bay and much of Lake Huron; Lake St. Clair; and the Wisconsin coast of Lake Michigan, from Green Bay to Escanaba in the Upper Peninsula.
The thickest ice, more than 2 feet thick, grows along Ontario’s bays: Black Bay and Nipigon Bay in the northwest region of Lake Superior.
What is the ice cap on Lake Superior?
As of March 2, 55.98% of Lake Superior was covered in ice.
Is Lake St. Clair frozen over?
No, but as of March 2, Lake St. Clair is 90.94% frozen.
How cold does Lake Erie freeze?
As of March 2, Lake Erie’s ice coverage rate was 74.15%.
How much ice covers Lake Huron?
As of March 2, 68.02% of Lake Huron was covered by ice.
Is Lake Michigan freezing over?
No. As of March 2, only 23.88% of Lake Michigan was frozen.
Is Lake Ontario frozen over?
Won’t. As of March 2, only 11.42% of Lake Ontario was covered by ice.
More information about the Great Lakes: Huge cracks form in Lake Erie ice. watch video
Is it rare for the Great Lakes to completely freeze over?
Yes, it is rare for an entire lake system to freeze over, although ice coverage can still be 90% or higher.
According to GLERL records, two lakes froze completely: Lake Superior in 1973 and 1996; and Lake Erie in 1978, 1979 and 1996.
According to Northern Michigan historical records, Lake Superior was nearly frozen during the 2013-14 ice season, with ice coverage of 92-96%.
What is the record ice coverage of the Great Lakes?
NOAA said the overall highest percentage of ice cover for all the Great Lakes was in 1979, when ice cover was 94.7%.
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Lake Superior has frozen over once since 1973, according to NOAA. In 1996, the lake’s ice coverage reached 100%.
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Lake Michigan’s ice coverage peaked at 93.2% in 2014.
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In 1996, Lake Huron was 98.2% ice covered.
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Lake Erie froze completely in 1978, 1979 and 1996.
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In 1979, Lake Ontario’s ice coverage rate was 86.2%.
When does Michigan’s Great Lakes freeze on average?
According to NOAA’s GLERL, here are the figures for 2025:
lake michigan
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Earliest date in 2025: December 2
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2025 latest date: April 14
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Ice cover peak date in 2025: February 21, reaching 33.5%
Lake Huron
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Earliest date in 2025: December 2
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2025 latest date: May 8
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Ice cover peak date in 2025: February 21, reaching 71.1%
lake superior
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Earliest date in 2025: December 2
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2025 latest date: May 11
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Ice cover peak date in 2025: February 21, reaching 45.6%
Lake Erie
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2025 latest date: April 22
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Ice cover peak date in 2025: February 20, reaching 95.8%
lake ontario
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Earliest date in 2025: December 6
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2025 latest date: April 19
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Ice cover peak date in 2025: February 20, reaching 26.1%
Which Great Lakes freeze the most in winter?
Historically, Lake Erie is the shallowest of the Great Lakes due to its shallow depth, which freezes and melts the fastest.
The Great Lakes Commission says Lake Erie has an average depth of about 62 feet, a maximum depth of 210 feet, and 871 miles of shoreline.
How deep are the Great Lakes?
Here are other average depths (from deepest to shallowest) for the Great Lakes, provided by the U.S. Environmental Protection Agency:
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Lake Superior: Average depth 483 feet, maximum depth 1,332 feet.
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Lake Michigan: Average depth 279 feet, maximum depth 925 feet.
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Lake Ontario: Average depth 283 feet, maximum depth 802 feet.
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Lake Huron: Average depth 195 feet, maximum depth approximately 750 feet.
Contact Sarah Moore@smoore@lsj.com
This article originally appeared in Lansing State Magazine: Great Lakes Ice Sheet. How frozen are the lakes?