The fire in British Columbia mentioned in the previous post continues to be the culprit, with smoke mixing to the surface when the overnight temperature inversion breaks. The satellite picture this morning shows smoke pouring down the Okanogan river valley.
Air quality in the area is expected to vary between Moderate and Unhealthy in the area with a slow improvement over the rest of today. Winds are expected to shift to the southwest and help return the smoke back to Canada with a "no thank you" note. But smoke lodged in more sheltered valleys might have a harder time getting scrubbed out, so expect areas of Moderate to USG to persist until tomorrow.
Rest of the state should see mostly Good air for the next few days, except close to some fires where Moderate or USG conditions can be expected during overnight hours.