Hydrometeorological log of the Upper Columbia Snow Laboratory

A summary of the hydrometeorological data gathered at the Upper Columbia Snow Laboratory during 1945-46 is presented. The Laboratory is located in the Rocky Mountains at Marias Pass, Montana, west of the Continental Divide. The field installations include 6 snow courses, 5 meteorological stations, 11 precipitation stations, and a streamflow measurement station. The tables, maps, and graphs present the data on radiation and reflection, temperature, degree-hours, wind, precipitation, snow depth and water equivalent, areal distribution of snow cover, streamflow, hydrological balance and various diurnal fluctuations. It was estimated that 19.7 inches of 38.5 inches of precipitation ran off in the streams. The remaining inches of precipitation are ascribed to loss by evaporation, ground water storage, underground seepage, and sampling error. Reflection of albedo amounted to 34 % of the radiation received.