About the Mendota Freeze Contest
On Saturday, November 15, 2025, Clean Lakes Alliance will kick off its 15th annual Mendota Freeze Contest. Calling on weather watchers and ice experts of all ages, the contest asks people to guess the official ice-on date for Lake Mendota. All people who guess the correct date will win a gift card to an area business. (Only one guess per individual. Multiple entries will be automatically disqualified. Official rules and regulations can be found here.)
Freeze statistics for Lake Mendota
- For insight into the Wisconsin State Climatology Office, which declares the lakes frozen each year, read more about lake ice records from Wisconsin State Climatology Office
- The Wisconsin State Climatology Office makes the official determination as to whether the lake is frozen. The climatologists use the same guidelines they have used for decades. This allows for a continuity in data collection. Read more: Determining ice cover on Madison’s lakes.
- For statistics about determining the freeze date and the Madison ice record, see History of freezing and thawing of Lake Mendota and Madison lakes ice summary.
- To test your knowledge of our lakes in the winter, take the frozen lakes quiz.
A look back at the 2024-25 season
Cold nighttime temperatures, combined with cold water and light winds, helped Lake Mendota officially freeze on December 25, 2024, as declared by the Wisconsin State Climatology Office. Two days later, on December 27th, Lake Mendota reopened as high temperatures climbed well into the 40s. The largest lake in the Yahara Watershed froze for the first time in the 2024-2025 winter season just five days after December 20th, which is the median ice-on date for Lake Mendota. The latest date ice-on has been declared is January 30th, and that took place in 1932.
The Wisconsin State Climatology Office requires ice to hold for a period of 24 hours before a lake can officially be declared frozen over. The December 25th freeze date is three weeks earlier than last winter’s January 15th freeze date. For statistics about determining the freeze date and the Madison ice record, see History of freezing and thawing of Lake Mendota and Madison lakes ice summary.
2024-2025 season winner!
For the 14th year in a row, Clean Lakes Alliance held its annual Mendota Freeze Contest, asking people to make a guess as to when the lake would officially freeze. Of the more than 1,300 people to enter the contest, 21 people guessed Lake Mendota would freeze on December 25th. Dan Standiford of Madison was the randomly selected winner. When Standiford was told he won the contest, he said, “I’ve been doing this for a long time and never even come close.” Standiford will receive $1,000 of gift cards courtesy of Lands’ End as the grand prize.
Contest Rules
Only one guess per individual. Multiple entries will be automatically disqualified. Official rules and regulations can be found here.
