PORTLAND, Ore. — Air quality in much of Oregon is set to improve starting Monday as wind coming in from the coast pushes lingering wildfire smoke further east, according to the Portland office of the National Weather Service, bringing an end to the hazy skies that have hung over the Portland metro area for the past few days.
Some parts of the Portland and Vancouver area were already seeing improvements as of late Monday morning, with most of the metro area's monitoring stations showing an air quality index back in the green "Good" range of 0-50 and a couple pockets still in the yellow "Moderate" range (51-100). The Air Quality Alert for the Portland metro area will be in effect until 5 p.m. Monday, according to the National Weather Service.
"By tomorrow you'll step outside and say 'my goodness, it's a whole lot better,'" said KGW meteorologist Chris McGinness. "And it will be better, but it's going to take a little while, and so our Monday, we remain under an Air Quality Alert cross the Portland metro area."
Other parts of southwest and central Oregon continued to have hazardous air conditions Monday morning — in some cases far worse than what Portland saw over weekend — and will take more time to improve.
The Cascades were mostly in the orange "Unhealthy for Sensitive Groups" (101-150) or red "Unhealthy" (151-200) ranges, and a large area from The Dalles and to Pendleton and south almost to Bend was in the purple "Very Unhealthy" (201-300) range, part of a swath of Very Unhealthy air that extended north across a large portion of central and eastern Washington.
The Dalles peaked at a rating of 243 Monday earlier morning and then slowly began to improve, McGinness said. The city should see a more meaningful drop back toward a healthy air quality range later Monday as west winds intensify, he added.
Hermiston also appeared to hit a peak of 267 late Sunday night, but has only seen minor improvement as of late Monday morning. The National Weather Service office in Pendleton predicted conditions would remain bad through the day on Monday but improve in the evening as smoke cleared out.
Wildfire smoke rolled into northern Oregon from two directions over the weekend, with new wind patterns moving smoke from fires burning in Washington and Canada south to join with smoke from fires in southwest Oregon and northern California, prompting Air Quality Alerts for Multnomah County, the Columbia River Gorge and central Oregon.
Despite having visibly hazy skies throughout the weekend, Portland escaped the worst of the smoke, with air quality generally in the yellow or orange ranges. KGW chief meteorologist Matt Zaffino noted last week that the smoke that reached the Portland area would likely stay aloft, adding to the haze but with comparatively less impact on ground-level air quality.
Lane County is still seeing smoke impacts from local wildfires such as the Bedrock fire, and Medford and Grants Pass were both rating orange or red on the air quality index on Monday due to wildfires in northern California. The Medford National Weather Service office said Sunday that the new wind patterns would lead to some improvements along the coast and in Douglas County.