Ice out dates should not be used to track ice thickness for recreational use. Ice conditions can change rapidly and should be checked frequently. Ice is Never 100% SafeReview ice safety tips.
The definition of lake ice out can vary from lake to lake. For the citizen observers reporting data, ice out occurs when the lake is completely free of ice. Or, it may be when it is possible to navigate from point A to point B. Ice out may also be when a lake is 90 percent free of ice. Observers use consistent criteria from year to year when reporting lake ice out dates.
Frequency of Updates
The map is not updated in real time. Updates to the lake ice out map are made as information is available.
The map below depicts historical median lake ice out dates using data archived by the DNR and the MPCA. Median is defined as the date where one half of the ice out dates were earlier, and one half of the ice out dates were later, than the presented date. To achieve lake-to-lake consistency, only 1950 - present dates were used to calculate the median. A marker is created for those lakes with ice out data whose period of record spans 20 or more years.
Hovering over the marker will cause the lake name and the median ice out date to be displayed. Clicking on the marker will produce an information window containing lake name, ice out summary statistics, and a link for obtaining all available historical ice out dates for the lake.
The map below depicts the earliest lake ice out dates found in data archived by the DNR and the MPCA. A marker is created for those lakes with ice out data whose period of record spans 20 or more years.
Hovering over the marker will cause the lake name and the earliest ice out date to be displayed. Clicking on the marker will produce an information window containing lake name, ice out summary statistics, and a link for obtaining all available historical ice out dates for the lake.
The map below depicts the latest lake ice out dates found in data archived by the DNR and the MPCA. A marker is created for those lakes with ice out data whose period of record spans 20 or more years.
Hovering over the marker will cause the lake name and the latest ice out date to be displayed. Clicking on the marker will produce an information window containing lake name, ice out summary statistics, and a link for obtaining all available historical ice out dates for the lake.
The map below depicts lake ice out date reports received by the DNR and the MPCA for . Hovering over the marker will cause the lake name and the ice out date to be displayed. Clicking on the marker will produce an information window containing lake name, ice out date, ice out summary statistics, and a link for obtaining all available historical ice out dates for the lake.