Minimal Ice, Maximum Snow: A Look at the Science Behind the Great Lakes’ Winters
Photo: MODIS satellite image of a lake effect snow event in the Great Lakes, caused by extensive evaporation as cold air moves over the relatively warm lakes. November 20, 2014. Credit: NOAA Great Lakes CoastWatch.
Living in western Washtenaw County, we’re fortunate to avoid the brunt of lake effect snow, but it remains one of Michigan’s most fascinating winter phenomena. This unique weather pattern highlights the diversity of conditions shaped by our state’s proximity to the Great Lakes.
Thus far, the winter of 2024-2025 has demonstrated the relationship between ice coverage on the Great Lakes and the intensity of lake-effect snow, particularly in Michigan. With historically low ice cover, the conditions were primed for several significant snow events, highlighting the direct impact of lake temperatures and atmospheric conditions on snowfall in the region.
Ice Coverage Trends
According to NOAA data, ice coverage across the Great Lakes was just 0.9% at the close of December 2024. By early January 2025, ice coverage had increased slightly to 4.7%, still well below historical averages for the season. These low levels of ice left much of the lake surfaces exposed, providing an abundance of moisture to fuel lake-effect snowstorms. This pattern is increasingly common as warmer winters reduce ice formation on the Great Lakes.
Michigan’s Experience with Lake Effect Snow

The minimal ice cover and Arctic air combined led to several intense snow events across Michigan. In late November and early December 2024, heavy lake-effect snow blanketed western Michigan. Communities in the snow belt along Lake Michigan were hit hard, with snowfall totals exceeding a foot in some areas. Although not directly adjacent to Lake Michigan, the City of Gaylord was in the lake-effect path and set a new single-day snowfall record of 24.8 inches over the Thanksgiving Day Weekend, surpassing the previous 17.0 inches from March 9, 1942.
The situation repeated in late December when another round of Arctic air swept across the region. With Lake Michigan’s surface largely unfrozen, moisture was readily available to generate snow. Snowfall rates reached up to 2-3 inches per hour in localized bands, causing hazardous conditions on roads and prompting travel warnings.
The Broader Impact in New York

While Michigan bore the brunt of several storms, New York’s Lake Erie and Lake Ontario regions also experienced heavy snowfall. Erie, Pennsylvania, set a single-day snowfall record of 22.6 inches, while Montague, New York, anticipated totals up to 3 feet in late December. These events illustrate how the same atmospheric dynamics affected other areas in the Great Lakes basin.
New York often experiences greater lake-effect snow amounts due to the longer “fetch” over the Great Lakes. “Fetch” refers to the distance that wind travels over open water. When cold winds align with the length of a lake, they traverse a longer distance over the water, allowing them to absorb more moisture.
This increased moisture content leads to more intense and concentrated snowfall when the air mass reaches land. Buffalo, New York, situated on the eastern tip of Lake Erie, is famous for its heavy snowfalls, often amounting to two feet or more. A snow event lasting from November 17-20, 2014, dubbed “Snowvember,” dumped over six feet of snow on the city.
The Science Behind the Snow

Lake-effect snow occurs when cold air masses pass over warmer, open water, picking up moisture that condenses and falls as snow. Ice coverage significantly moderates this process. When lakes freeze over, the insulating ice layer blocks moisture from evaporating into the air, effectively shutting down the lake-effect snow machine. Conversely, low ice coverage, as seen in 2024-2025, amplifies snowfall potential by allowing continuous moisture transfer.
This winter’s snow events illustrate the role of ice coverage as a key factor in lake-effect snow intensity. Western Michigan, a region already accustomed to heavy snowfall, saw prolonged and intense storms due to the extended period of open water on Lake Michigan.
Looking Ahead
Scientists speculate that as climate trends point toward continued warming and reduced ice coverage, the Great Lakes region could see more frequent and intense lake-effect snow in the near term. However, over the long term, warming temperatures may shift precipitation from snow to rain in some areas, altering the winter landscape in Michigan and beyond.
Sources
- NOAA Great Lakes Environmental Research Laboratory
- Great Lakes Integrated Sciences and Assessments (GLISA)
- WeatherNation (“Low Ice Coverage Means More Lake Effect Snow”)
- AP News (“What is Lake Effect Snow?”)
- New York Post (“Great Lakes Region Braces for Feet of Snow to Kick Off New Year”)