When Does Harriet Lake Freeze? Typical Ice-In Dec 10, Ice-Out Apr 7
Harriet Lake in Hennepin County, Minnesota usually freezes over around Dec 10, and usually has ice-out around Apr 7, based on Minnesota DNR ice observations recorded between 1996-2024. That works out to roughly 247 days of open water a year. These are typical dates across many winters, not a forecast — individual years swing by weeks in either direction.
Ice record for Harriet Lake
| Typical freeze-up (ice-in) | Dec 10 |
| Typical ice-out | Apr 7 |
| Earliest freeze-up on record | Nov 25, 1996 |
| Latest freeze-up on record | Jan 14, 2024 |
| Earliest ice-out on record | Mar 7, 2017 |
| Latest ice-out on record | May 2, 2018 |
| Open-water season | ~247 days |
| Winters observed | 160 |
| Location | Hennepin County, Minnesota |
These are dates, not an ice-safety reading
A typical freeze-up date tells you when Harriet Lake has usually iced over — it does not tell you the ice is safe, and we hold no thickness measurement for this or any lake. The Minnesota DNR is explicit that no ice is ever completely safe: thickness varies across a single lake, and current, springs, aerators, and insulating snow all weaken it. Ice that held a truck last week may not hold a person today.
Read the ice-thickness guidelines before going out, and check current conditions with the Minnesota DNR ice-safety page and local bait shops, which track conditions lake by lake.
How much the timing varies
Ice-out on Harriet Lake has landed as early as Mar 7, 2017 and as late as May 2, 2018 — a spread of weeks around the Apr 7 median. Freeze-up has ranged from Nov 25, 1996 to Jan 14, 2024. That year-to-year swing is why a median date is a planning tool, not a schedule. Freeze-up is driven by accumulated cold after the lake turns over in fall; ice-out by late-winter air temperature, sun angle, and how much snow sits on top of the ice reflecting it. Harriet Lake carries an overall water-quality grade of D — the full breakdown is on the lake report.
Source: Minnesota DNR Climate Office ice-in / ice-out records, observations from 1996-2024.