Even if the air starts out well below freezing along and near the coast, this easterly wind can advect milder air inland, causing frozen precipitation to change to rain. Freezing Rain Rain droplets that fall into a shallow layer of cold air near the earth's surface can freeze upon contact with the ground, leaving a coating of glaze . This is known as freezing rain. Freezing rain most often occurs when mild, moist air is advected over a cold polar or Arctic air mass near the Earth's surface. Freezing rain causes dangerous weather conditions for travelers .
Rain can freeze on anything it contacts, including roads.
It is extremely difficult to drive on a road glazed over with ice. Bridges and overpasses, which typically freeze quicker than other surfaces, are particularly hazardous to drivers. Power outages are also common in an ice storm. The weight of ice and freezing rain often causes downed power lines and tree limbs, leaving thousands in the affected area without electricity, sometimes for days at a time. Snow Snow is frozen precipitation in the form of a six-sided ice crystal.