| Term: | Freezing rain |
| Definition: |
Rain, the drops of which freeze on impact with the ground or with objects at or near the ground. CanadaNCA
Rain, the drops of which freeze on impact with the ground or with objects on the earth's surface or with aircraft in flight. NSIDCCryosphere Rain that falls as a liquid but freezes into glaze upon contact with the ground. NOAA-NWS Rain that freezes on impact to form a coating of clear ice (glaze) on the ground and on exposed objects. ECCCanada Rain that freezes upon impact, forming a surface coating of glaze, or after percolating below the glacier surface. IHPGlacierMassBalance Supercooled raindrops which freeze on impact to form a coating of clear ice on the ground and/or on exposed objects. WMOHydrology Rain that falls in liquid form but freezes upon impact to form a coating of glaze upon the ground and on exposed objects. In aviation weather observations, this hydrometeor is encoded ZR. While the temperature of the ground surface and glazed objects is typically near or below freezing (0C or 32F), it is necessary that the water drops be supercooled before striking. Freezing rain can sometimes occur on surfaces exposed to the air (such as tree limbs) with air temperatures slightly above freezing in strong winds. Local evaporational cooling may result in freezing. Freezing rain frequently occurs, therefore, as a transient condition between the occurrence of rain and ice pellets (sleet). When encountered by an aircraft in flight, freezing rain can cause a dangerous accretion of clear icing. AMSglossary A type of precipitation. Occurs when liquid rain hits a cold surface and then immediately freezes into ice. For this to occur, a surface temperature inversion is usually required. In such an inversion, the surface must have a temperature below freezing, while the temperature of the atmosphere where the precipitation forms is above freezing. PhysicalGeography Rain, the drops of which freeze on impact with the ground or with objects on the earth's surface or with aircraft in flight. SPRI GCW |