Ethereal ice structures swirl alongside Chicago during extreme cold snap fueled by polar vortex — Earth from space
QUICK FACTS
Where is he? Chicago, IL [41.85802928, -87.57938545]
What’s in the photo? Ice swirls on the shore of Lake Michigan
Which satellite took the photo? Landsat 8
When was it taken? January 24, 2025
This striking satellite photo shows undulating ribbons of ethereal ice swirling like turbulent clouds on the surface of Lake Michigan, alongside a snow-covered Chicago. The winter scene occurred during an extreme cold snap triggered by changes in the polar vortex, experts say.
The greater Chicago area is home to approximately 9.5 million people and is near the southern end of Lake Michigan, the third largest of the Great Lakes, which covers an area of approximately 22,300 square miles (57,750 square kilometers) across Illinois, Indiana, Wisconsin, and Michigan.
Between January 19 and 24, 2025, Windy City and other areas of the eastern United States were hit by an unusual cold snappartially triggered by a sudden expansion of the polar vortex — the persistent zone of cold, low-pressure air circulating in the upper stratospheres over the Arctic. During this period, temperatures in Chicago fell as low as minus 33 degrees Fahrenheit (minus 36 degrees Celsius), according to the National Oceanic and Atmospheric Administration (NOAA).
This sudden drop in temperature, combined with strong offshore winds, caused ice to form around the coastline and push outwards, creating magnificent whirlpools. These flowing ribbons look a lot like clouds from above, but they’re made entirely of ice, according to NASA Earth Observatory.
In total, about 20 percent of Lake Michigan was covered in ice when the satellite photo was taken, which is just above average for this time of year, according to NOAA. Great Lakes Environmental Research Laboratory (GLERL).
Although lake ice is common in January, ice extent on Lake Michigan does not normally reach its maximum until February or March. It’s also more common to see uniform layers of ice rather than the fluid patterns seen in this image.
In this case, the darker, wispy ice near the lake shores likely accumulated into thicker offshore formations with rough edges that appear whiter from above, Jia Wangice climatologist at GLERL, told the Earth Observatory.
Other Great Lakes were also affected by the cold snap, including Lake Erie, which saw up to 80% of its surface frozen, according to GLERL. Erie’s ice was so thick and emerged so quickly that a Canadian freighter was stuck there for three days, according to the New York Times.
This isn’t the first time satellite photos have revealed something unusual about Lake Michigan. In 2024, aerial images helped researchers identify more than 40 mysterious craters scattered throughout the lake bed, which currently have no definitive explanation.
Low temperatures and strong winds around Chicago can also cause other unusual winter displays, such as bizarre sand sculptures resembling chess pieces along Lake Michigan beaches, known as “hoodoos,” which form when frozen chunks of sand are exposed to strong gusts.
For more incredible satellite photos and astronaut images, check out our Earth seen from space archives.
