Reliability of Precipitation Measurements as Related to Exposure

Abstract

A subjective classification system was developed to evaluate the reliability of measurements of precipitation occurring primarily as snow in relation to the exposure of the gage. This system was used in classifying 30 sites above 8,000 ft in Utah where both precipitation measurements and snow surveys are made. A comparison of the winter precipitation (October-March) with the water equivalent of the snow on the ground as of 1 April showed that the differences in amounts were related to the exposure classifications. Data on dual installation of precipitation gages at protected and unprotected sites are given. The protection afforded by the installation of a windshield where light winds are observed is also illustrated.