The Measurement of 1 min Rain Rates from Weighing Raingage Recordings

Abstract

A method of obtaining accurate 1 min rain rate distributions from weighing raingage records is described. This source of data is of interest because of the large number of weighing raingage recordings available from the U.S. Weather Service. A special measuring instrument has been built with which data can be read with greater accuracy than can be obtained by direct reading of the chart. Even with this increased accuracy, accurate rain rates cannot be obtained without further processing of the data as described herein. Without this processing the errors are large, the larger errors occurring at the higher rain rates. The method of data processing employed allows an estimate of the accuracy of the measurements. The method has been used to measure 100 years of rainfall data and the resulting 5-year rain rate distributions for 20 locations in the continental United States are included.