I hadn't heard that there has been a decline in snowfall, it's pretty stark in the Pacific West:
https://www.epa.gov/climate-indicators/climate-change-indica...
https://www.epa.gov/climate-indicators/climate-change-indica...
Anyway, there are quite a few NOAA SNOTEL sites all over that have reliable data and for sure snow pack is on a decline, and there's also USDA NRCS who use that data and publish agricultural specific interpretations of it. Further, due to budget constraints, some of these data may stop being tracked and produced altogether.
https://www.wcc.nrcs.usda.gov/ftpref/gis/images/co_swepctnor...
https://www.wcc.nrcs.usda.gov/ftpref/gis/images/mt_swepctnor...
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