Lake Michigan breaks the ice-coverage record. The 1977 record of 93.1% was surpassed this weekend, with a new record of 93.29%. Last Thursday, ice cover on the Great Lakes was the second highest cover on record, with just over 92%. However, as of this past Sunday, ice-coverage melted down by a percentage. It is expected to continue to decrease due to this week's warmer weather. The current record for Great Lakes ice-coverage is about 95% in 1979.