When Does Lake Minnetonka Freeze? Ice-In Dates

Short answer: in the Minnesota DNR record, Lake Minnetonka has locked up between November 25 and January 2. The DNR has 46 winters on file, from 1978 to 2025. The middle date is December 8. That is our own arithmetic on the DNR list.

Seven of the 46 dates fall in November. Six fall after December 20, including one in January. Most winters land in the first half of December. The record is a window and not a promise.

No ice is ever 100% safe. Check it yourself.

An ice-in date is not a green light. It is the day an observer says the whole lake is frozen and stays that way. It says nothing about thickness where you plan to stand.

What the records show

The DNR State Climatology Office keeps the state's lake ice-in records. Minnetonka is listed as DNR lake ID 27013300, in Hennepin County.

• Dates on file: 46 winters between 1978 and 2025. There are no entries for 2015 or 2023.
• Earliest: November 25, in both 1991 and 1996.
• Latest: January 2, 2002. The latest in December is December 26, 1997.
• Median: December 8. Sorted from earliest to latest, the middle dates are both December 8 (2021 and 2022).
• Recent run: 15 dates from 2009 to 2025. Three are in November (2013, 2014, 2018) and one is December 24 (2020).

Two notes on the DNR feed. Its summary "earliest" field shows November 25, 1996, which matches our count. Its summary field for the median is not usable, so we computed the median from the list of dates. For 2006 the feed holds two entries, December 4 from the MPCA and December 5 from the DNR. We counted the DNR date once.

The January 2, 2002 entry sits between the 2000 and 2002 rows. There is no December entry for 2001, so we read it as the lock-up for that winter.

Lake Minnetonka ice-in dates

The years missing from the list are 2015 and 2023. We do not guess what happened in those years.

A big lake with many bays

The DNR LakeFinder lists Minnetonka at 14,206 acres, with a maximum depth of 113 feet and an average depth of 30 feet. It says the lake is made of many connected bays and has a complex shoreline. Shallow bays often lock up before open water does. Deep, open water takes longer. Do not assume the whole lake matches a bay.

The DNR also keeps small records for parts of the lake. These come from the MPCA.

In 2018 the Upper Lake record says November 20. The whole-lake record says November 28. In 2024 the whole-lake date is December 12 and the Upper Lake date is December 20. The two records do not move together every year. Three or eight dates are too few to call a pattern.

What "ice in" means here

The DNR defines ice-in for its citizen observers as the day the entire lake is frozen over and the ice cover remains through winter. Observers do not report ice thickness. The definition can vary from lake to lake.

The DNR says it does not measure ice thickness on Minnesota lakes. It says ice-in dates should not be used to track ice thickness for recreation. It does not post the current year's dates in real time, for safety, because the ice cover may not be permanent for the season.

Ice thickness minimums (Minnesota DNR guideline)

Source: Minnesota DNR ice thickness guidelines. These are for new, clear ice only.

• Under 4 inches: stay off.
• 4 inches: ice fishing or other activities on foot.
• 5 to 7 inches: snowmobile or small ATV.
• 7 to 8 inches: side-by-side ATV.
• 9 to 10 inches: small car or SUV.
• 11 to 12 inches: medium SUV or small truck.
• 13 inches: medium truck.

White ice is only about half as strong as new, clear ice. The DNR says to double these numbers on white ice. Ice is seldom the same thickness across a lake. It can be two feet thick in one place and one inch thick a few yards away. The DNR says these guidelines assume average equipment weight and solid, clear ice. You are responsible for knowing the weight of your vehicle, gear and crew.

For more on thickness, read our ice thickness chart and safety guide.

Parked vehicles need more ice

The numbers above are for moving loads. The DNR says a load that sits longer than two hours needs thicker ice. It says to park at least 50 feet apart and move vehicles every two hours. If the ice is not thick enough to drive on and park away from shore, do not park on it at all.

How to check current ice

1. Do not rely on a date. Check thickness where you are standing.
2. Drill a hole. Measure clear ice, not slush or white ice.
3. Drill again every few steps. Ice changes fast.
4. Stay off pressure ridges, cracks, and open water. See pressure ridges, cracks and slush on ice.
5. Wear a flotation device and carry picks and a rope.
6. Tell someone where you are going and when you will be back.

Early ice is the risk window. First ice looks solid and often is not. Read how to read first ice before your first walk.

The DNR says currents, narrow areas and bottlenecks, wind, snow cover, sun and shade, and plant decay all change how strong ice is. A lake with many bays and narrows has plenty of those. Check each bay and each crossing on its own.

We did not find an official source for a typical start date for hardwater season or plowed road access on Minnetonka. So we do not give one. Check the DNR and local notices for current conditions.

No ice is ever 100% safe. Check it yourself.

FAQ

When does Lake Minnetonka freeze?

In the DNR record it has frozen between November 25 and January 2, with a median of December 8, across 46 winters from 1978 to 2025. That is not a promise for any year.

What is the earliest Lake Minnetonka has frozen?

November 25, in 1991 and 1996. The latest on file is January 2, 2002. An earlier or later date is possible.

Is first ice safe once the lake is locked up?

Not by date alone. The DNR says 4 inches of new, clear ice is the guideline for walking, and double it on white ice. Measure it yourself.

How thick should ice be for a snowmobile or ATV?

The DNR guideline is 5 to 7 inches of new, clear ice for a snowmobile or small ATV, and 7 to 8 inches for a side-by-side. Check it yourself.

Does the DNR measure ice thickness on Lake Minnetonka?

No. The DNR says it does not measure ice thickness on Minnesota lakes. Your safety is your responsibility.