Air quality alert: Wildfire smoke may be unhealthy for days in Seattle

Hints of haze high in the skies above Seattle portend thicker smoke in the days to come while catastrophic wildfires burn in Spokane.

Smoke was staying aloft Monday morning while there was a northwesterly flow, keeping particulates high enough that air quality wasn’t yet degraded around Puget Sound, said National Weather Service meteorologist Dana Felton.

But that likely won’t last long. 

By Monday afternoon, the Puget Sound and Olympic Region clean air agencies had issued air quality alerts covering King, Kitsap, Pierce, Snohomish and Thurston counties through 5 p.m. Wednesday

“Air quality conditions are expected to worsen throughout (Monday) as smoke begins to mix down to the surface,” the alert read.

The flow was expected to turn northeasterly late Monday, pulling in the smoke from the wildfires, Felton said. The smoke could cause the air quality to degrade to “unhealthy” levels in Seattle and reduce visibility.

“Doesn’t look very good,” Felton said. 

Tens of thousands of people were evacuated from their homes in Spokane over the weekend as a trifecta of wildfires exploded in size around the edges of the city, and hundreds of structures have been lost. About a dozen other major wildfires burning east of the Cascades grew by about 30% in a few days. Dry conditions exacerbating fire risk aren’t going to dissipate anytime soon. 

As smoke rolls in Tuesday morning, it’ll settle into the city for days, Felton said, as the northeasterly flow will continue pulling smoke toward the city through Thursday while “there really won’t be much of a mechanism to get it out.”

Tuesday will also be hot, with highs around 85, Felton said. 

Wednesday and Thursday were expected to reach near 90 degrees in the Puget Sound region, but the smoke will be so thick that it could actually cool those temperatures off a few degrees as it blocks the sun, Felton said. 

The low-level flow pattern is expected to turn around Thursday night, Felton said, meaning air quality could improve come Friday.

People with health concerns should try “limiting time outside, avoiding strenuous activity, and following tips for cleaner indoor air,” according to the National Weather Service.

For more safety information, visit seattle.gov/wildfire-smoke-safety.