2021 Ice Out

Detroit's 2021 ice-out date was on April 4, 2021.  Though Little Detroit was substantially ice free a couple of days before, as usual, a large mass of ice remained on Big Detroit. On Sunday mid-afternoon a mass of residual floating ice was still clinging along the East Shore of Big Detroit, but the lake was more than 95% ice-free, in accordance with Minnesota DNR guidelines for ice-off determination. 

The April 4th date is about two weeks earlier than the average of the previous 30 years.   It is noteworthy that there is no trend in ice-out dates over this period

April 4th is the 5th earliest date in the last thirty years, with earlier dates in 2012 (March 23), 2016 (March 29), 2010 (April 2), and 2000 (April 3).   Twice in that period ice-outs were more than a month later, in 1996 (May 5), and 2013 (May 12). 

This year the lake was covered with ice for 139 days, about 5 days shorter than the thirty year average. The longest ice--cover duration was 1996 with 177 days and the shortest in 2000 with 110. There is no discernable trend in duration of ice-cover for this period either, though the average for the entire 111 year record is about ten days longer than recent decades

Lake ice rolls onto the mile-long beach shoreline of Detroit Lake on April 1, 2021. (Michael Achterling / Tribune)