The central Brooks Range has long, severe winters and relatively short, cool summers. The entire region receives continuous sunlight during the summer for at least 30 days. Conversely, winter visitors will experience long, cold periods of darkness and twilight.
The south side of the Brooks Range below 2,500 feet is generally a sub-arctic climate zone. Precipitation is low, averaging 12-18 inches in the west and 8-12 inches in the east. Snow can fall any months of the year, averaging 60-80 inches. The average maximum and minimum July temperatures are 70F and 46F, respectively. Thunderstorm activity is common during June and July, and June through September is generally the wettest time of year. Prevailing winds are out of the north. Freezing temperatures may occur at any time of the year, but particularly from mid-August on. Average minimum and maximum January temperatures are -10F and -30F but frequently reach -50F.
The north side of the Brooks Range has an arctic climate. Mean annual temperatures are colder than on the south side. Maximum and minimum February temperatures range from 33F to -47F. The warmest month, July, has a 60F maximum and 40F minimum. Precipitation is extremely light, about 5-10 inches per year, making this essentially an "arctic desert". Snow has been recorded in every month of the year, and the annual average is 45 inches. Prevailing winds are greatly modified by local terrain.
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