Radar Determination of Snowfall Rate and Accumulation

Abstract A unique method that provides for relating radar-measured reflectivity factors to snowfall rates at the ground is presented. Data were provided by a CPS-9, 3.2 cm radar from six 1978 Massachusetts snowstorms A best-fit power-law relationship between hourly-averaged snowfall rate (depth) and radar reflectivity factor is determined. This derived relationship is found to be Z = 5.07S1.65 with a correlation coefficient of 0.91. With this relationship hourly snowfall rates are found to be accurate to within +41 to −29% and total storm snowfall accumulation to within +44 to −31%.