Enjoy Friday’s summer-like weather while you can. With a predicted high of 80 degrees or more, it will be the last day of unseasonably warm weather for at least a week and likely much longer, says KPLU meteorologist Cliff Mass.
He says the recent string of high temps is ending with a bang.
“It’s amazing; The temperatures will get up to 80, maybe even lower 80s in a few locations, and completely dry,” said Mass, a professor of atmospheric sciences at the University of Washington.
“In fact, we’ve gone through an unusually warm and amazingly dry period; It’s hardly rained the last two weeks,” he said.
But everything changes on Saturday.
A Gradual Cooldown
At first, it will be pretty gradual, Mass predicts, with temperatures sliding down from the 80-degree range to the lower 70s. “Maybe 70 degrees,” he said. And there will be showers coming into the south, but they may not reach Seattle.
“An upper-level low will go below us. It’ll push some showers maybe to Seattle, but not much further north,” he said.
Mini-Ridge Sunday
Then on Sunday, a mini-ridge will move in, bringing still lower temperatures with it, “but it’ll be dry, maybe in the 60s,” Mass said.
The really big cool down will come toward the middle or end of next week, he says.
Flow Transition Changes Everything Next Week
“A very strong upper-level low will descend from the Gulf of Alaska, right over the Northwest,” Mass said. “Temperatures will drop into the lower 60s, maybe upper 50s and then we’ll get some real rain.”
And that’s the start of a longer period of what will feel more like normal Northwest spring weather.
“There’s a major flow transition in the atmosphere, so everything’s getting reconfigured, and I think this is going to be there for a while,” Mass said.
As for Friday’s spike to 80-plus degrees?
“You’re not going to see that kind of warmth for at least for a few weeks.”
For a discussion of why spring brings so much windy weather to the eastern slopes of the Cascade Mountains and why industry and scientists are studying it, you can click on the “play” icon at the top of this post.
The weekly KPLU 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 KPLU 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.
