Owing to its location 320 miles (515 km) north of the Arctic Circle, Barrow's climate is cold and dry, and is classified as a polar climate (K�ppen ET). Winter weather can be extremely dangerous because of the combination of cold and wind, while summers are cool even at their warmest.
Weather observations are available for Barrow dating back to the late 19th century. Currently there is a National Weather Service (NWS) Office and a National Oceanic and Atmospheric Administration (NOAA) Climate Monitoring Lab in Barrow. The United States Department of Energy (DOE) also has a climate observation site in Barrow as part of its Atmospheric Radiation Measurement (ARM) Climate Research Facility.
Despite the extreme northern location, temperatures at Barrow are moderated by the surrounding topography. The Arctic Ocean is on three sides, and flat tundra stretches some 200 miles (300 km) to the south. Thus, there are no wind barriers, and there are no protected valleys where dense cold air can settle or form temperature inversions in the lower atmosphere in the way that commonly happens in the Interior between the Brooks Range and the Alaska Range.
Nonetheless, Barrow experiences the lowest average temperatures in Alaska. Although it is rare for Barrow to record the lowest temperatures statewide during cold waves, extremely low wind chill and "white out" conditions from blowing snow are very common.
Temperatures remain below freezing from early October through late May. The high temperature is above freezing on an average of only 120 days per year, and there are temperatures at or below 0 �F (?18 �C) on an average of 160 days per year. Freezing temperatures, and snowfall, can occur during any month of the year.
In terms of precipitation, Barrow has a desert climate, and averages less than 5 inches (127 mm) "rainfall equivalent" per year, given that one inch of rain possesses approximately equal water content to 12 inches (30 cm) of
