This data set includes daily snow water equivalent (SWE) observations for the historical record to September 2019 at 1,065 stations in the western U.S. and western Canada. Remote telemetry stations measure snowpack by relating measurements of the overlying snowpack mass to the water depth equivalent. The data were obtained from the Natural Resources Conservation Service, the California Department of Water Resources, Alberta Environment, the British Columbia Ministry of Environment, and the Yukon Government Water Resources Branch. Two levels of data are provided. The file snowPillowSWE_westernNA_level1_ncc.nc has been formatted but not quality controlled. The file snowPillowSWE_westernNA_level2_ncc.nc has been formatted and quality controlled. Both files are in netCDF format. The level 1 product provides daily SWE from January 1, 1960, to September 1, 2019 (21,794 days; row dimension) for 1,065 stations (column dimension). The level 2 SWE product is formatted by water year (October 1 to September 30) starting on Oct. 1, 1960 and ending on September 1, 2019, for the 1,065 stations and 59 years. Thus, it is of dimension [366 days,1065 stations, 59 years]. See the metadata in the netCDF files for information on all variables. Missing data are indicated by NaN. Please refer to the following publication for more information on the data and QA/QC methods: Musselman, K.N., N. Addor, J. Vano, and N.P. Molotch (2021). Winter melt rates portend widespread declines in snow water resources. Nature Climate Change. DOI: 10.1038/s41558-021-01014-9