NOAA/PSL Catalog http://psl.noaa.gov/thredds/catalog/Datasets/snowcover/catalog.html

Dataset Size Last Modified
     Folder  snowcover   --
         snowcover.mon.ltm.nc 781.4 Kbytes 2018-02-23T15:36:18Z
         snowcover.mon.mean.nc 19.25 Mbytes 2016-04-26T21:36:45Z

NOAA/PSL at NOAA PSL see Info
THREDDS Data Server [Version 4.6.15-SNAPSHOT - 2020-01-28T04:01:10+0000] Documentation