Andrew Smith said on his YouTube post:
“Each year as warmer temperatures begin to thaw the lake ice it begins to drift more freely in the lake. As the winds shift directions or storm fronts move in, it blows across the large surface area of the sheets of ice. The ice then begins to drift until it contacts either the shore or another large sheet of ice.
Although it tends to happen on yearly basis, the timing and intensity is [sic] hard to predict.”