After months of smoke-choked skies across the Pacific Northwest, fall rain and seasonal weather shifts have brought significant improvement to air quality across Oregon, Washington, and Idaho. Public health officials are now beginning to assess the full health toll of one of the worst wildfire smoke seasons on record in the region.

A Season of Unprecedented Smoke Exposure

The 2026 fire season exposed millions of PNW residents to prolonged periods of unhealthy and hazardous air quality. At its peak in early August, Portland ranked among the worst major cities worldwide for air quality, with the Oregon Department of Environmental Quality issuing advisories covering 27 of Oregon's 36 counties simultaneously.

Washington communities east of the Cascades — particularly Spokane, the Tri-Cities, and the Wenatchee Valley — faced even more severe exposure, with smoke from the Sinlahekin, Little Giant, and dozens of smaller fires blanketing eastern Washington for weeks at a time. AQI readings in the 200 to 300+ range ("Very Unhealthy" to "Hazardous") were recorded repeatedly across the region.

Idaho communities in the Boise metropolitan area and southwestern counties were also severely impacted, with the Idaho Department of Environmental Quality issuing advisories covering Ada, Adams, Boise, Canyon, Elmore, Gem, Owyhee, Payette, Valley, and Washington counties during peak events.

Health Impacts

Healthcare systems across the PNW reported sustained elevated emergency visits for respiratory illness, asthma exacerbations, and cardiovascular events linked to fine particulate matter exposure during smoke events. The 2026 season is expected to produce a substantial dataset on population-level health impacts from wildfire smoke that researchers and public health officials will be analyzing for years.

  • Fine particulate matter (PM2.5) from wildfire smoke penetrates deep into the lungs
  • Prolonged exposure increases risk of respiratory and cardiovascular events
  • Children, elderly, and those with underlying conditions are most vulnerable
  • AQI levels in some communities exceeded "Hazardous" thresholds for multiple consecutive days

What Residents Can Do Now

While the acute smoke crisis has eased, public health officials remind residents that prescribed burning this fall may occasionally produce localized smoke impacts. Residents with respiratory conditions should continue to monitor AirNow.gov and their local DEQ or state environmental agency for air quality forecasts. Stocking up on N95 or P100 masks and having a clean air room in your home remain best-practice recommendations for all PNW households heading into future fire seasons.