Long Knife Peak (9789 ft) is located in the Clark Range, Glacier National Park in the U.S. state of Montana. Though much of the mountain slopes extend into the Canadian Province of British Columbia, the main summit is in the U.S. Long Knife Peak rises more than a vertical 1 mi above Upper Kintla Lake. It is also the most northerly peak and land area in the contiguous United States above 9000 ft. Long Knife Peak is on an east west ridgeline identified as the "Boundary Mountains" on the USGS 7.5 minute topo quad and this extended ridge, with peak 8864, also contains the most northerly named (numbered) peak and land area in the contiguous United States above 8000 ft.

Climate

Based on the Köppen climate classification, Long Knife Peak is located in an alpine subarctic climate zone characterized by long, usually very cold winters, and short, cool to mild summers. Temperatures can drop below −10 °F with wind chill factors below −30 °F. The summit of Long Knife Peak has a tundra climate (Köppen ET) or an Alpine climate.