Tucker Sno-Cat on the rim of Crater Lake. Mr. Tucker is in the hat behind the cat and there is even a park ranger squatted on the track. Probably late 40s.
Crater Lake has only totally frozen over just a few times in modern history. The big freeze was in 1949 when several park employees walked out to Wizard Island on the ice. Here is a Tucker Sno-Cat at Discovery Point probably in 1949. photo courtesy of Lloyd Smith