Mendota Freeze Contest
“Winter” descended quickly on Madison in 2019, with colder than normal temperatures recorded in October and November. Higher than average amounts of snow were also reported each month. But when will Lake Mendota freeze? Every year, the Mendota Freeze Contest calls attention to the year-round importance of our lakes on our local quality of life.
On December 1, 2019, Clean Lakes Alliance will kick off its eighth annual Mendota Freeze Contest. Weather watchers and ice experts of all ages will be asked to guess the official ice-on date for Lake Mendota. A winner will be randomly selected from all entrants who guess the correct freeze date.

When will Lake Mendota freeze?
- 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.
- Read more about the 2018 freeze declaration.

A look back at 2018
Cool nights, light winds, and cold water helped Lake Mendota officially freeze on Saturday, December 15th, 2018. Lake Mendota, the largest lake in the Yahara Watershed, froze eight days after the smallest lake in the watershed, Lake Wingra, which officially froze on December 7th, 2018. Lake Monona officially froze on December 11th, 2018.
The Wisconsin State Climatology Office officially declared Lake Mendota open again on December 21st, 2018. Lake Mendota has had double freeze dates only six other times since data collection first began in the winter of 1852-53. Other winters with two freeze dates are: 1936-37, 1968-69, 1977-78, 1978-79, 1984-85, and 2001-02.

2018 winner of the Mendota Freeze Contest
Clean Lakes Alliance’s annual Mendota Freeze Contest asks people to make a guess as to when Lake Mendota will officially freeze. Amy Lemley of Thompson, Georgia submitted the first correct guess for Lake Mendota’s first freeze date of the season. She received a $1,000 Lands’ End gift card as a grand prize. Lemley said she entered the Clean Lakes Alliance contest after hearing about it from her daughter-in-law, who lives in the Madison area.

Contest Rules
Only one guess per individual. Multiple entries will be automatically disqualified. Official rules and regulations can be found here.
