Climate Watch

Strong east winds are a feature of western Alaska winter weather, and not infrequently, but especially the second half of winter, the winds are not the result of a strong storm in the northern Bering Sea, but rather caused by the region caught between cold high pressure to the north and milder low pressure far to the south. But rarely have such winds been so strong for so long as occurred February 1 to 3, 2022. The weather pattern responsible for this historic event was not in any sense unusual: strong high pressure from North Slope southward across the Interior, while at the same time there was broad low pressure across the southern Bering Sea into Bristol Bay. This pressure difference is the large-scale driver of the winds, which are in turn influenced by the presence (or absence) of mountains and valleys and their orientation relative to the overall wind direction. What was unusual during the first days of February was the persistence of the pressure pattern: neither high or low pressure moved much, and so the winds just kept on blowing. And the weather fronts remained far to the south of the Seward Peninsula, so there were little more than some high thin clouds.

For most areas it was really the multi-day duration of the winds that was most outstanding. There have been days with stronger winds and higher gusts, but not for so long. At Nome Airport, the average sustained wind speed on both February 2 and 3 was over 30 mph. This is the only time in the past 50 years that back-to-back days have had an average speed above 30 mph. Not surprisingly, the average wind speed of 29.7 mph for the first three days of February is also the highest three-day wind speed since the early 1970s (at least). Unalakleet was by far the windiest community. Wind speeds averaged above 40 mph on February 2 and 3. Sustained winds were 50 mph or higher for 25 hours and peak winds above 60 mph for 35 hours, with a maximum gust of 74 mph. Brevig Mission was also very windy. In contrast, the windiest days at Koyuk, White Mountain and Shishmaref had average wind speeds of under 20 mph and peak winds were less than 40 mph.