How_it_works.txt
Within 15 days: the daily snowfall forecast at mid-mountain.
15–35 days out: the usual amount for those dates, nudged at half strength by ECMWF's 51-run extended forecast.
Beyond 35 days: the usual amount for those dates over 33 winters, adjusted by how the mountain and its region did in the five strong El Niño winters. The range covers 8 of every 10 past winters.
History is ERA5 reanalysis via Open-Meteo, scaled to each mountain's published annual average.