A Critique of the Climatic Record of “Water Equivalent of Snow on the Ground” in the United States

Abstract The water equivalent of snow on the ground (SWE) has been measured daily since 1952 at National Weather Service first-order stations whenever snow depth exceeded 5 cm (2 in). These data are used in snowmelt analyses, snow climatology, and snow load design calculations for budding codes. Problems with this measurement that may affect data quality include 1) inconsistent methods of measurement among stations and within many stations' records, 2) unrepresentative and inconsistent locations of measurement, 3) a six-hour lag between daily measurement of snow depth and SWE, and 4) numerous errors in the climatic record of extreme SWE values. These data have not been viewed critically in the literature and are not subjected to rigorous quality control at the National Climatic Data Center. Suggestions are made for improving the quality of SWE data.