What conditions are needed for freezing rain to occur?

Freezing rain occurs when a layer of warm air is sandwiched between colder air at the surface and higher altitudes. Precipitation falls as snow or rain from the warmer air, but when it reaches the cold surface layer, it supercools and freezes upon contact. This typically requires a temperature inversion, where temperatures increase with altitude, and sufficient moisture in the atmosphere. The result is a glaze of ice that can accumulate on surfaces, creating hazardous conditions.