Warmer, above freezing temperatures have been occurring more regularly across Wisconsin and the Lake Michigan area since about March 7. Since reaching a record ice concentration of 93.29% on March 8th on Lake Michigan, the ice has dwindled considerably. The latest ice concentration measurement from March 19th was 57.89%.
The below animation of high resolution satellite images of Lake Michigan shows the large decrease in ice cover from March 10 to March 12. The high temperature in Milwaukee on March 10 was 55o, and 49o on March 11.
As of March 18, a large area of ice remained over eastern Lake Michigan. Watch the above animation to see how the ice location varies with the prevailing winds.
The below graph shows how the Lake Michigan ice concentration peaked on March 8th, and has since fallen to around 60%.
After Friday, Temperatures will remain below normal for much of the coming week so only a small change is expected in the total ice concentration on Lake Michigan through the last days of March.
National Weather Service - Milwaukee/Sullivan