Extremes and Trends

It hit 100°F in the state once, in Fort Yukon in 1915. Fairbanks regularly breaks 90°F in July. It gets cold in Fort Yukon too, dropping as low as -78°F (Alaska’s record low is -82°F, recorded in aptly named Coldfoot in 1989). Any wind at all at that temperature would make you feel even colder, if that’s possible.

Thompson Pass near Valdez gets quite a bit of snow, holding the records for the most in 24 hours (5 feet), a month (25 feet), and a year (81 feet). But Barrow, at the tip of the proverbial “frozen wasteland,” got just three inches of snow in 1936–1937. An average of almost 13 feet of rain falls in Ketchikan every year—they call it “liquid sunshine.” But again, one year Barrow squeaked by with only an inch.

Though Alaska retains the reputation of the Great Frozen North, a distinct warming trend has had a noticeable effect on the state. Temperatures warmed abruptly in the summer of 1977 and have remained unusually warm ever since, throughout all the seasons. For example, meteorologists report that in the Interior, only on rare occasions over the past 20 years has the mercury dropped much below -40°F. Also, the temperature of the permafrost has risen several degrees.

For the latest research, visit the website of the University of Alaska Fairbanks International Arctic Research Center (www.iarc.uaf.edu).

Climatic Zones

It’s possible to generalize about Alaskan weather and distinguish three climatic zones: coastal maritime, interior, and Arctic. The main factor affecting the southern coasts is the warm Japanese Current, which causes temperatures to be much milder than the norm at those latitudes. This current also brings continuous rain as humid Pacific air is forced up over the coastal mountains. For example, it rains in Juneau two out of three days.

However, these mountains shield the Interior plateaus from the maritime air streams, so yearly precipitation there is low—a mere 15 inches. The Interior experiences great temperature extremes, from biting cold in winter to summer heat waves. The mountains also protect the coastal areas from cold—and hot—Interior air masses.

The Arctic zone is characterized by cool, cloudy, and windy summers (averaging 50°F) and cold, windy winters—though not as cold as in the Interior.

Based at the University of Alaska Fairbanks, the Alaska Climate Research Center (http://climate.gi.alaska.edu) has detailed information on the state’s climate, along with current weather conditions.

© Don Pitcher from Moon Alaska, 10th Edition