'Tis the season for Northwest dust storms. Here's a primer on how and why we get them. | KNKX

'Tis the season for Northwest dust storms. Here's a primer on how and why we get them.

Feb 28, 2020

People in Western Washington have enjoyed plenty of mild, warm days and sunshine lately — typical weather for late winter and early spring. Suddenly, we’re shedding layers and searching for our sunglasses.

But in Eastern Washington and Oregon, early spring marks the onset of what can be a terrifying phenomenon: Northwest dust storms that dramatically reduce visibility and air quality when winds pick up.

KNKX weather expert Cliff Mass notes a major dust storm hit the area around Kennewick just last Sunday.

“It was so bad south of Kennewick around I-82, that the road was closed for hours. There was a series of accidents and reduced visibility due to the dust storm,” Mass says. “And this is something we often see starting this time of the year, this is the beginning of dust storm season in Oregon and Washington."

MORE FREQUENT IN MODERN TIMES

We’ve always had them. Lewis and Clark noted some dust in the air when they came through the area in the early 1800s. But Mass says they’re becoming more frequent because of the way modern human civilization has colonized the land.

“The big problem is that we have disturbed the surface," he says. "We have a huge amount of agricultural fields in Eastern Washington — and to some extent in Eastern Oregon.”

Extensive ploughing usually takes place in late fall and early spring.

The scene on the highway near Kennewick last Snuday, as captured by a traffic web cam.
Credit WSDOT screenshot

“And then we get a wind event,” Mass says. It could come from a cold front moving through (as it did on Sunday, with winds as strong as 60-70 mph.) Or gusts could come with the powerful thunderstorms that are typical later in the spring. 

“These dust storms can reduce visibility to only 100 feet or 200 feet. And often we’ve had major accidents — often chains of accidents — as cars crash into each other,” Mass says. “So, it is actually a major safety issue.”

TECHNIQUES TO REDUCE DUST STORMS
Mass says the conditions in Eastern Washington are almost always dry enough for these kind of dust storms to happen, except in winter, when it rains there.

He says there’s no reason to think that the winds are increasing. But the dust storms do seem more frequent. He thinks it’s because humans have cleared so much land and made the soil more vulnerable to blowing away.

There are agricultural practices, such as no-till farming, that can help in the long run, Mass says: “Where you don’t plough up the land, you actually put the seeds into the soil without disturbing the surface — that can have a big effect.”  

CLIFF’S FORECAST

Friday: Cloudier in the afternoon as a potent cold front approaches. Fog will subside and rain will start and continue overnight.

Saturday: Unstable air behind the front will produce rain showers and sunbreaks in the lowlands and lots of snow in the mountains, through Saturday afternoon. “I’m expecting at least 6-12 inches from 3,000 feet up,” Mass says.

Sunday: A ridge of high pressure moves in, bringing more sun and partly cloudy skies with temperatures around 50. “So Sunday’s definitely going to be the better day."

Next week: A series of systems comes through. Cooler. Rain every other day, and a lot more snow in the mountains.

Editor's note: This story has been updated with the correct audio. A previous version included a file that was added in error.

Weather with Cliff Mass airs at 9:02 a.m. Friday, right after 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 podcasts of Weather with Cliff Mass shows, via iTunes or Google Play.