Freezing Rain happens when precipitation falls in liquid form as raindrops and immediately freezes as it hits most any surface. This can occur as rain or snow falls through a deep layer of warm air aloft. This warmer layer is usually 2,000 to 3,000 feet above the sub-freezing layer. This turns the snow to rain or keeps the rain in liquid form. As the rain falls, it passes through a very cold, but shallow layer of cold air at the surface and once it hits the ground, trees, cars or other items it freezes and forms a coating or glaze over the surfaces.