A new method is described for reconstructing snowfall from observed snow depth records, meteorological observations, and the NASA Seasonal-to-Interannual Prediction Project Catchment Land Surface Model (NSIPP CLSM). This method is developed and tested at Reynolds Creek Experimental Watershed (RCEW) in southwestern Idaho. The intended application of the method is for the pan-Arctic land mass, where estimates of snowfall from gauges is highly uncertain but where there are many decades of historical snow depth and surface air temperature records. Results from the test site show that using the NSIPP CLSM and observations from RCEW, snowfall can be accurately reconstructed based on how much snow must have fallen to produce the observed snow depth.