Brace For Possible Snow On New Year’s Eve, Then A Major Cold Wave In Washington

Dec 30, 2016

With partly sunny skies and temperatures expected to get into the low 40s on Friday in western Washington, knkx weather expert Cliff Mass says enjoy it while you can.

“Wow – that’s going to seem warm in a few days,” he said of Friday’s temps. A major and sustained cold spell is expected to start over the weekend, with a good chance of snow showers in many parts of the region on New Year’s Eve.

Transition Saturday, With Some Snow Into Sunday

Mass says an upper-level trough of low pressure will be approaching Saturday, bringing clouds into the region.

“So it will start out okay, but as the afternoon wears on, it’ll get pretty thick,” he said. “And then we’re expecting some precipitation over Saturday night into Sunday morning.”

Mass says temperatures will be dropping at the same time.  “So I think that later on Saturday evening into Sunday morning, it’ll be cold enough where the precipitation is heavy enough, to give us a few snow showers. And we could even get as much as an inch of snow,” he said.

He expects the snow to be localized mostly “within the Puget Sound convergence zone, somewhere north of Seattle, so Seattle to Everett, that area, I think will be the hot spot. There’ll also be a chance of getting some snow up towards Whatcom County.”

Mass says he doesn’t expect heavy snow, but there’s a good chance we’ll get half an inch to an inch, especially north of the city, before it ends. That will be sometime around breakfast on Sunday morning.

“So, people have to be aware of that. It’s not going to be any kind of big snow event, but the roads could get a little bit of snow,” he said. However, he says the recent relative warmth will keep it from getting very dangerous.  “I don’t think there’ll be a lot of ice issues on New Year’s Eve, that’s very important,” he said.

Extremely Cold Next Week

Mass says as the storm moves past, a surge of very cold air from the Arctic will move in over our region.

“This is going to be impressive,” he said. “This will be the coldest air and the most sustained cold air that we’ve had in probably 5-6 years.”

He says Monday – Friday,  highs will not get much above freezing next week, with lows down into the low 20s.  

“Maybe even the teens in the colder areas,” he said. “So we’re talking about a real serious cold spell for us around here.”

But he says on the up side, this pattern will bring a lot of sun with it during the days.

“We’re going to get offshore flow, easterly flow that’s going to be extremely dry, so it’ll be cold and very dry and sunny during the afternoons,” Mass said.

To hear the forecast along with Cliff’s discussion of where the cold surge is coming from and how the local terrain affects it as it moves in, you can click on the “play” icon at the top of this post.

The weekly knkx feature 'Weather with Cliff Mass’ airs every Friday at 9 a.m. immediately following ‘BirdNote’, and twice on Friday afternoons during ‘All Things Considered’. The feature is hosted by knkx environment reporter Bellamy Pailthorp. Cliff Mass is a University of Washington professor of atmospheric sciences, a renowned Seattle weather prognosticator, and a popular weather blogger. You can also subscribe to a podcast of ‘Weather with Cliff Mass’ shows.