Ice Out on Lake Minnetonka

The warm steady wind on Saturday took out most of the ice on the main lake however Sundays lack of wind was unable to finish it off.

Monday morning 98% of the ice was gone. I think the official ice out day will be 04/05/2004.

Until next winter.



The official (whatever that means) date is 4/6/04.


Can someone explain the ice out process?
Why does it seem that 12" of ice will be there one day and not the next? It doesn't seem to slowly melt away. As it deteriorates, does it get heavier than water and sink to the bottom?

It's complicated...

It's a complicated process. I'm looking forward to hearing what people say.

First off, ice is always less dense that liquid water (at least in the temperature regimes we're interested in):

One reason thick ice can disappear so rapidly is that it sometimes it becomes very weak (ex. due to "honycombing") although it still remains quite thick. In this case, much of the volume of the "ice" is actually water. A good wind can often break weak ice up very rapidly. I've personally watched a lake here in Madison go out over the course of lunch. The volume of ice blown to shore from a 2-3 mile fetch of lake was remarkably small (a mound perhaps 3 feet high).


Geoff Sobering
DN US-5156