When Does Gull Lake Freeze? Ice-In Dates

Short answer: in the Minnesota DNR record, Gull Lake (Cass County, near Brainerd) has locked up between November 14 and December 22. The record holds 39 distinct ice-in dates across 36 winters, from 1955 to 2017. The middle date is December 1. Eighteen of the 39 dates fall in November. The other 21 fall in December.

The median and the counts are our own arithmetic on the DNR date list. Treat the window as a rough guide 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 record shows

The DNR State Climatology Office keeps the lake ice-in records. This one is for Gull (DNR lake ID 11030500). The DNR lake survey data lists the lake in Cass County, at about 10,000 acres, with a maximum depth of 80 feet. Several lakes in Minnesota share the name Gull. This guide covers only the Cass County lake.

• Dates on file: 40 entries, 39 distinct dates (2004 lists the same date twice).
• Years covered: 1955 to 1978 (24 winters, from the DNR lakes database) and 1998 to 2008 plus 2017 (12 winters, from the Minnesota Pollution Control Agency, MPCA).
• Earliest: November 14, in 1959 and again in 1976.
• Latest: December 22, 1998.
• Median: December 1 (our count).

Look at the gap. Nothing is on file for 1979 to 1997, 2009 to 2016, or 2018 on. The record is old at one end and thin at the other. Recent winters are not in it, so it cannot tell you about the lake as it behaves now.

One note on the DNR feed. Its summary fields can differ from the list of dates. We used the list and computed the earliest, latest and median from it.

Gull Lake ice-in dates

Four winters have more than one entry. In 2004 both entries say Dec. 14. In 2005 the entries are Nov. 30 and Dec. 6. In 2006 they are Dec. 1 and Dec. 6. In 2007 they are Dec. 1 and Dec. 10. The DNR does not say why. It may be different parts of the lake or different reporters. We list each date once and do not pick between them. If you use only the earlier date for each winter, or only the later one, the median is still about Dec. 1.

How the dates spread

Of the 39 dates, 18 are in November and 21 are in December. The most common single date is November 29, with six entries, all from 1956 to 1967. Four dates fall on or after December 14: Dec. 14, Dec. 20 (twice) and Dec. 22. All of those are from 1998 and later.

That last point is a clue and not a rule. The 1998 to 2008 winters were reported by a different source than the 1955 to 1978 winters. The two groups may not use the same yardstick. Do not read a trend into it.

What "ice in" means here

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

So an ice-in date tells you roughly when a lake locked up. It does not tell you what is safe to walk on today. On a lake near 10,000 acres, one date can hide a lot. Bays, narrows and points freeze and thaw on their own schedules.

Ice thickness minimums (Minnesota DNR guideline)

Source: MN DNR ice thickness guidelines. These apply to 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.
• 16 to 17 inches: heavy-duty truck.
• 20 inches or more: heavy-duty truck with a wheelhouse shelter.

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. The DNR notes 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. The DNR also says it does not measure ice thickness on Minnesota lakes.

Parked vehicles need more ice

The numbers above are for moving loads. For a load that sits longer than two hours, the DNR lists thicker minimums. A loaded vehicle between 2,200 and 4,400 pounds needs 16 inches. A vehicle between 4,400 and 6,600 pounds needs 18 inches. The DNR says to park at least 50 feet apart and move vehicles every two hours. A sleeper house or other fixed shelter is a stationary load, so plan for more ice, not less.

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 the edges of 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 more in first ice: how to read it. For a full breakdown by load, see the ice thickness chart and safety guide.

The DNR lists temperature, snow cover, currents, narrow areas and bottlenecks, sun and shade, fish communities and plant decay as things that change ice strength. Check for them on a lake with this much shoreline.

Do not drive onto ice because someone else did. A plowed road is not proof of safe ice. Measure for your own load.

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

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

What we will update

Iceline will update this guide as new Gull Lake entries are added to the DNR record. Until then, remember that the earliest date on file is November 14, and treat any first ice as unproven until you measure it.

FAQ

When does Gull Lake freeze?

In the DNR record it has frozen between November 14 and December 22, with a median of December 1, across 39 distinct dates from 1955 to 2017. That is not a promise for any year.

What is the earliest Gull Lake has frozen?

November 14, in both 1959 and 1976. The latest on file is December 22, 1998. The record has big gaps, so an earlier or later date is possible.

How thick should ice be to walk on?

The Minnesota DNR guideline is 4 inches of new, clear ice for ice fishing or other activity on foot. Use 5 to 7 inches for a snowmobile or small ATV. Double the numbers on white ice. Check it yourself.

Is there a recent ice-in record for Gull Lake?

Not much. The DNR list has one date after 2008 (December 8, 2017) and nothing for 1979 to 1997. Do not lean on it for this winter.

Does the DNR measure ice thickness on Gull Lake?

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