Whoops, this site is better, uses a map for those of us unfamiliar with the names.
http://www.or.nrcs.usda.gov/snow/maps/oregon_sitemap.html
for reference:
Took a look at Marion Forks. When the snow depth gets over 100 inches, the number shows up as -99.9 . Marion Forks is near Detroit which has 13 feet of snow.