Better add a tin of Joe Brown’s Carmel Corn and some Pendleton blankets to that holiday gift list. What once looked like a charming prospect of a white Christmas is now shaping up as a serious winter storm that could dump more than half a foot of snow on Portland early next week.
Forecast models released Dec. 21 by the Portland office of the National Weather Service show a 90% chance that the city gets at least an inch of snow between Dec. 26 and 29.
But that’s the low range of the forecast. Portland could receive up to 11 inches in some models.
More and more model guidance suggests a much colder and likely snowier weather pattern will take hold across northwest Oregon and southwest Washington late in the weekend and early next week. #pdxtst #orwx #wawx (1/3) pic.twitter.com/gOObJfE10G— NWS Portland (@NWSPortland) December 21, 2021
“It really looks like we are going to get some accumulating snow,” says NWS meteorologist Colby Neuman. “It’s a 50-50 shot whether we get 4 inches of snow. It’s the flip of a coin.”
The expected snowfall is part of a winter weather system that could paralyze holiday travel across the Pacific Northwest, especially in the Cascade and Sierra Nevada mountain ranges. Neuman expects difficult travel conditions on Interstate 84 in the Columbia River Gorge, and says snow along Interstate 5 in the Willamette Valley is “definitely not out of the question.”
He advises caution. “Anyone traveling Saturday night to Sunday and onward should plan on snow through the Cascades through much of the next week,” he says.
Such confidence about snow and snarled traffic five days out in the forecast is unusual. But Neuman says the forecast models align: The temperature will drop below freezing on Christmas as precipitation arrives, and it’s unlikely to climb again as the week continues.
“This isn’t going to be like the snow event we had a few nights ago, where it melted off,” he says. “It’s going to be really cold and windy across the Portland metro.”
Multnomah County officials open winter warming shelters when forecasters predict an inch or more of snow. The Joint Office of Homeless Services hasn’t yet announced the locations of those shelters for next week; when it does so, the information will be posted here.