Lake Superior Could Completely Freeze Over This Winter

Last came closest in 1994

Lake Superior hasn't completely frozen over in two decades.

But an expert on Great Lakes ice says there's a "very high likelihood" that the three-quadrillion-gallon lake will soon be totally covered with ice thanks to this winter's record-breaking cold.

The ice cover on the largest freshwater lake in the world hit a 20-year record of 91 percent on Feb. 5, 1994.