Weathercatch: More wintry weather is on tap through December
If you live in the Inland Northwest, an insulated jacket and a sturdy snow shovel will come in handy during the next few weeks. Following an abnormally cold, snowy November, similar conditions appear to loom for the month of December.
The National Weather Service’s Climate Prediction Center is favoring cooler and wetter conditions to extend at least through December in the Pacific Northwest, according to its recent outlook report.
So basically, November’s weather gave us a preview. Spokane saw its seventh-snowiest November in more than 150 years, with 18.5 inches of snowfall, compared to the month’s normal amount of 6.2 inches. Also, temperatures ran at least 10 degrees colder than normal on 12 days. Nov. 29 was the coldest, with a high of 25 degrees and a low of only 6. The last time Spokane saw a chillier November was in 2000.
As we wrap up December’s first week, the weather still feels more like mid-winter than early in the season. Since Nov. 28, a parade of wintry storms has marched across the Pacific Northwest in fits and starts. What’s more, temperatures continue to run below normal for this time of year.
The pattern is largely being fueled by an atmospheric and oceanic phenomenon thousands of miles away: La Niña.
“How very La Niña… to see these frequent weather systems moving through,” the National Weather Service Spokane wrote on Facebook last weekend.
La Niña is characterized by cooler than normal sea-surface temperatures in the tropical Pacific Ocean that can alter weather patterns around the planet. In the United States, typical La Niña winters tend to be cooler and stormier in the Pacific Northwest, and hotter and drier in the desert Southwest and lower half of California.
And now, La Niña is looming large. Although other atmospheric factors influence the season’s weather, a strong La Niña is usually a major player. For example, during winter 2010-2011, an amped-up La Niña pattern fueled cold, stormy conditions across the Pacific Northwest. A rare blizzard warning was issued in the Inland Northwest, snow drifts formed 2 feet high and an arctic air mass sent temperatures to -3 in Spokane.
As we usher in a cold, snowy start to December, classic La Niña conditions are in place. More snow is expected Thursday, followed by a heavier snowfall overnight and into Friday. Then another bout may come this weekend.
Being that we’re already in an icebox surrounded by snow and more is on the way, a white Christmas certainly appears likely.
Nic Loyd is a meteorologist in Washington state. Linda Weiford is a writer in Moscow, Idaho, who’s also a weather geek. Contact: ldweiford@gmail.com.