Doppler Radar Relationships for Hail at Vertical Incidence

Abstract

Relationships are derived which can be used in the analysis of Doppler radar spectra of hail at vertical incidence to find storm updrafts and hailstone size distribution parameters. It is assumed that the hail is spherical and homogeneous, that it is either dry or coated with a film of liquid water, and that it is distributed with respect to size according to a truncated exponential spectrum. The relations found in this work are applied to the Doppler spectra of several workers and are found to produce results which are in good agreement with observation. It is also shown how these relations can be used in the analysis of conventional, single-wavelength radar data to accurately determine hail mass and kinetic energy fluxes.