Winters tend to be long and harsh and summers short and cool. Climate Long, severe winters are typical of this ecoregion. Winds are persistent and strong throughout the region. Approximately ten weeks are frost-free each summer. All weather stations in the region are located at the lower elevations.
Annual precipitation is heaviest in late summer and early fall, occurring as rain.
Mean annual precipitation ranges from 250 mm to 510 mm at lower elevations, with 100 cm to 190 cm of snowfall occurring. Mean annual precipitation for the highlands, interpolated from lowland data, exceeds 1,000 mm, and snowfall may be as much as 250 cm. C. Average daily minimum temperature in summer ranges from 1 C to 6 C, and maximum from 13 C to 17 C. Temperatures are generally warmer in the southern portions of the region. The ecoregion has narrow strips of coastal lowlands that grade into extensive uplands of broad convex hills and flat divides. Small, isolated groups of rugged mountains occur in a few locations.