When Does Upper South Long Lake Freeze? Typical Ice-In Dec 3, Ice-Out Apr 15
Upper South Long Lake in Crow Wing County, Minnesota usually freezes over around Dec 3, and usually has ice-out around Apr 15, based on Minnesota DNR ice observations recorded between 1998-2024. That works out to roughly 232 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 Upper South Long Lake
| Typical freeze-up (ice-in) | Dec 3 |
| Typical ice-out | Apr 15 |
| Earliest freeze-up on record | Apr 1, 2010 |
| Latest freeze-up on record | Dec 23, 1998 |
| Earliest ice-out on record | Mar 13, 2024 |
| Latest ice-out on record | May 10, 2013 |
| Open-water season | ~232 days |
| Winters observed | 56 |
| Location | Crow Wing County, Minnesota |
These are dates, not an ice-safety reading
A typical freeze-up date tells you when Upper South Long 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 Upper South Long Lake has landed as early as Mar 13, 2024 and as late as May 10, 2013 — a spread of weeks around the Apr 15 median. Freeze-up has ranged from Apr 1, 2010 to Dec 23, 1998. 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. Upper South Long Lake carries an overall water-quality grade of B — the full breakdown is on the lake report.
Source: Minnesota DNR Climate Office ice-in / ice-out records, observations from 1998-2024.