Cloud and Precipitation Bands

The term “precipitation band” describes an area of precipitation that originates from updrafts that are either non-convective or weakly convective (not associated with thunderstorms), where the precipitation area is sufficiently elongated to have a discernible orientation. Precipitation bands are common within extratropical and tropical cyclones, but also develop along topographical and geographical features, such as mountains, islands, coastlines, and lake shores. The study of precipitation bands in various parts of the world, largely utilizing radar, has led to the development of taxonomies to classify bands. Precipitation bands can form as the result of processes operating individually or in tandem, including frontogenesis, deformation and/or convergent flow, conditional, potential, or moist symmetric instability, boundary-layer convergence, gravity waves, topographic effects, and/or microphysical interactions. Understanding precipitation bands is vital because they can have a substantial effect on local weather, causing extended periods of rain or heavy snowfall over specific regions.