Climate Watch

By Rick Thoman Alaska Climate Specialist Alaska Center for Climate Assessment and Policy International Arctic Research Center/University of Alaska Fairbanks

With February comes rapidly increasing daylight and increased opportunities for outdoor activities. The outlook for February for western Alaska from NOAA’s Climate Prediction Center calls for increased chances of significantly above normal temperatures and precipitation.

But what does that actually mean?

Well, for starters, climate outlooks are not like weather forecasts. Weather forecasts, whether on your phone, on the radio or TV, provide expected values of specific elements, for example the wind speed this afternoon or high temperature tomorrow. Climate outlooks are quite different, in that the outlooks are only for categories for monthly and seasonal averages (temperatures) or totals (precipitation) that are in relation to a longterm normal. Usually we have three categories: Significantly below normal, near normal and significantly above normal. Although it’s usually implicit, the Climate Prediction Center outlooks actually provide the chances of all three categories. Of course, to be really useful we need to have an idea of what “normal” is and how that varies in a particular month or season. In the graphic, I’ve combined all these elements for the February outlook for Nome. So, while it’s clear that the Climate Prediction Center thinks it’s quite unlikely to be colder than normal in February, there’s still a one in five chance that it will be.

As for total precipitation (rain plus melted snow), even though the significantly-above-normal total is the most favored of the three categories, it’s only slightly (five percent) more likely than a significantly below normal total.

Although the February average temperature is not quite as low as

January for most of western Alaska (the exceptions being the Bering Strait and St. Lawrence Island), the February average temperature in Nome has the lowest monthly average about one in three winters. Daily temperatures rise only about two degrees from the start to the end of the month. Daily extremes likely show no trend during the month.

Since 1907, February temperatures have ranged from 48°F in 1986 to -42°F eight different times, most recently in 1978.

Over the past 25 years February has had the highest average wind speed of any month of the year, due in part to the incredibly stormy February 2019. Average February precipitation is about one inch, very close to the other mid-winter months and more than in March and April.

One thing is certain: We can count on daylight increasing rapidly in February, when we’ll gain three hours of sunshine in four weeks.