Precipitation and Environmental Conditions during Accretion in Canadian East Coast Winter Storms

Abstract

Precipitation and environmental conditions occurring during accretion in Canadian east coast winter storms are described and investigated. Accretion is generally associated with snow, freezing rain, and ice pellets within saturated conditions. Precipitation types are sometimes invariant but usually evolve during individual accretion events. Accretion events are also generally associated with moderate wind speeds (average of 7.5 m s?1) and warm temperatures (between ?1° and 0°C are most common). Remote sensing of particle shapes and terminal velocities are capable of identifying some of the features of these precipitation types. Model calculations indicate that a detailed understanding of precipitation characteristics, such as the nature of wet snow, is needed to accurately simulate accretion.