[1] The nearest higher neighbor is West Unicorn Peak, 0.79 miles (1.27 km) to the southeast.

Foss Peak is located in the marine west coast climate zone of western North America.

[3] Most weather fronts originating in the Pacific Ocean travel northeast toward the Cascade Mountains.

As a result, the west side of the Cascades experiences high precipitation, especially during the winter months in the form of snowfall.

[3] Because of maritime influence, snow tends to be wet and heavy, resulting in avalanche danger.