Topographic relief is significant as the summit rises 1,550 meters (5,085 feet) above Brynildsen Creek in 2.5 kilometers (1.55 mile).

[3] Based on the Köppen climate classification, Big Snow Mountain is located in the marine west coast climate zone of western North America.

[5] Most weather fronts originate in the Pacific Ocean, and travel east toward the Coast Mountains where they are forced upward by the range (Orographic lift), causing them to drop their moisture in the form of rain or snowfall.

As a result, the Coast Mountains experience high precipitation, especially during the winter months in the form of snowfall.

This climate supports glaciers on the north, east and west slopes of Big Snow.