Its nearest higher peak is Pelion Mountain, 0.77 km (0 mi) to the east.

The first ascent of the mountain was made on July 25, 1960, by Dick Chambers, Jack Bryan, and Howie Rode via the east ridge.

[4] 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.

The months July through September offer the most favorable weather for climbing Ossa.