Piegan Mountain

Piegan Mountain (9225 ft) is located in the Lewis Range, Glacier National Park in the U.S. state of Montana. Piegan Glacier is located in a cirque immediately southeast of the summit.

Geology
Like other mountains in Glacier National Park, Piegan Mountain is composed of sedimentary rock laid down during the Precambrian to Jurassic periods. Formed in shallow seas, this sedimentary rock was initially uplifted beginning 170 million years ago when the Lewis Overthrust fault pushed an enormous slab of precambrian rocks 3 mi thick, 50 mi wide and 160 mi long over younger rock of the cretaceous period.

Climate
Based on the Köppen climate classification, it is located in an alpine subarctic climate zone with long, cold, snowy winters, and cool to warm summers. Temperatures can drop below −10 °F with wind chill factors below −30 °F.