Why is air quality so bad in Seattle and Portland right now?

Seeing wildfire smoke and air quality warnings trending for Washington and Oregon. What's causing it and how long is it expected to last?

Wildfire smoke from fires burning in Washington state has been drifting into the Pacific Northwest in early August 2026, pushing air quality in Seattle and Portland into unhealthy ranges for multiple days, combined with unusually hot conditions. Local reporting has generally described relief as expected by the end of the week as weather patterns shift, though exact timing depends on wind direction and how quickly the underlying fires are contained, so it's worth checking a live regional air quality index rather than assuming a fixed end date. This kind of smoke event has become a fairly regular late-summer occurrence in the Pacific Northwest over the past several years, as wildfire season in the western US and Canada has generally grown longer and more intense — smoke can travel and affect air quality hundreds of miles from the actual fire.