When Does the Ice Go Out on Outlet of Onamia Lake on the Rum River? Typical Ice-Out Apr 4
Outlet of Onamia Lake on the Rum River in Mille Lacs County, Minnesota usually has ice-out around Apr 4, based on Minnesota DNR ice observations recorded between 2015-2019. These are typical dates across many winters, not a forecast — individual years swing by weeks in either direction.
Ice record for Outlet of Onamia Lake on the Rum River
| Typical ice-out | Apr 4 |
| Earliest ice-out on record | Mar 30, 2015 |
| Latest ice-out on record | Apr 20, 2019 |
| Winters observed | 4 |
| Location | Mille Lacs County, Minnesota |
These are dates, not an ice-safety reading
A typical freeze-up date tells you when Outlet of Onamia Lake on the Rum River 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 Outlet of Onamia Lake on the Rum River has landed as early as Mar 30, 2015 and as late as Apr 20, 2019 — a spread of weeks around the Apr 4 median. 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. Outlet of Onamia Lake on the Rum River carries an overall water-quality grade of A — the full breakdown is on the lake report.
Source: Minnesota DNR Climate Office ice-in / ice-out records, observations from 2015-2019.