This ecoregion covers a zone of climate transition from coastal to interior conditions in northwestern British Columbia and southern Yukon. The ecoregion falls within the rain shadow of the Coast Mountains. Precipitation decreases moving inland, and temperatures are moderated throughout the year by the influence of maritime air masses. The mean annual temperature for the area is approximately -1°C with a summer mean of 10°C and a winter mean of -13°C. The mean annual precipitation is 500-600 mm. The ecoregion is composed of a combination of three distinct vegetation zones: alpine tundra dominated by low-growing heather, dwarf birch, willow, grass, and lichen; subalpine forests of alpine fir, white spruce, and an occasional Engelmann spruce; and closed boreal forests of black and white spruce. Aspen and lodgepole pine regenerate after fire at mid to lower elevations. The ecoregion encompasses the mountainous areas leeward of the St. Elias Mountains and a portion of the Kluane Ranges. It is a region with subdued mountains and wide valleys. Permafrost is discontinuous and sporadic with generally low ice content. Soils range from Brunisolic and Regosolic with some Cryosolic soils in alpine regions to Dystric and Eutric Brunisols in subalpine and boreal sections of the ecoregion. Characteristic wildlife includes grizzly and black bear, Stone's and Dall's sheep, mountain goat, pika, wolf, wolverine, ptarmigan, moose, spruce grouse, and deer. Land use presently includes outfitting, hunting, outdoor recreation, mining and mineral exploration. The extreme northwestern portion of the ecoregion in British Columbia, west of the Haines Road, falls within the Tatshenshini-Alsek Wilderness Park. Telegraph Creek is the only permanent settlement in the ecoregion. The population of the ecoregion is approximately 60.
This ecoregion is part of the Boreal Cordillera ecozone.