Ice storms are caused by freezing rain. The raindrops move into a thin layer of below-freezing air right near the surface of the earth, allowing them to freeze on contact to the ground, trees, cars and other objects. Ice accumulates when super-cold rain freezes on contact with surfaces that are below freezing point.
On Saturday, Feb. 29, 2020, a major Ice Storm hit Lake Erie at Hoover Beach in Hamburg, New York. The Lakeside homes were completely encased in ice, the residents say the ice was anywhere from 1 to 3 feet thick!