ATTU ISLAND, ALASKA

This climate type is dominated by the winter season, a long, bitterly cold period with short, clear days, relatively little precipitation mostly in the form of snow, and low humidity. It is located north of the humid continental climate, from about 50° to 70° N, in a broad swath extending from Alaska to Newfoundland in North America and from northern Scandinavia to Siberia in Eurasia. In Asia the Siberian anticyclone, the source of continental polar air, dominates the interior of the continent. The North American representative of this climate is not as severe but is still profoundly cold. Mean monthly temperatures are below freezing for six to eight months, with an average frost-free period of only 50-90 days per year, and snow remains on the ground for many months. Summers are short and mild, with long days and a prevalence of frontal precipitation associated with maritime tropical air within traveling cyclones. Annual precipitation totals are mostly less than 500mm (19.69 in), with a concentration in the summer.

The Köppen Climate Classification subtype for this climate is "Dfc". (Continental Subarctic Climate).

The highest recorded temperature in Attu Island is 90.0°F (32.2°C), which was recorded in March. The lowest recorded temperature in Attu Island is -15.0°F (-26.1°C), which was recorded in October.

The average amount of precipitation for the year in Attu Island is 52.6" (1336 mm). The month with the most precipitation on average is October with 6.6" (167.6 mm) of precipitation. The month with the least precipitation on average is May with an average of 2.9" (73.7 mm). There are an average of 197.0 days of precipitation, with the most precipitation occurring in November with 20.0 days and the least precipitation occurring in June with 11.0 days.

In Attu Island, there's an average of 76.4" of snow (0 cm). The month with the most snow is February, with 16.9" of snow (42.9 cm).