Air quality across much of the Pacific Northwest is improving this weekend after weeks of smoke-choked skies driven by dozens of large wildfires burning across Oregon, Washington, and Idaho. While conditions remain variable near active fire areas, the arrival of cooler temperatures and light precipitation is bringing meaningful relief to millions of residents who endured prolonged periods of unhealthy air throughout August.

Oregon DEQ Smoke Advisories

The Oregon Department of Environmental Quality (DEQ) issued an Air Quality Advisory for Smoke that covered multiple counties across eastern, north-central, and western Oregon during the final days of August and first days of September. The advisory warned that wildfires burning in the region, combined with stagnant atmospheric conditions, were causing air quality to reach unhealthy levels at times for sensitive groups and the general public.

DEQ officials stated that the advisory was expected to last through at least the afternoon of Wednesday, September 2, 2026, for most affected counties. Deschutes County transitioned to an intermittent smoke advisory — a less severe designation — on the evening of Tuesday, September 1, reflecting improving conditions in the Bend area.

As of September 6, Portland’s air quality index (AQI) has returned to the “Good” category. However, communities closer to active fires — particularly in Umatilla, Morrow, Wheeler, and Wallowa counties in northeastern Oregon — may still experience periods of smoke-impacted air as large fires continue to burn with incomplete containment.

Washington and Idaho

Smoke from multiple large fires in eastern Washington, including the Sinlahekin Fire and the Spokane Complex, pushed air quality into “Unhealthy” and “Very Unhealthy” categories across much of eastern Washington during the peak fire weather period in early August. The Puget Sound region and Seattle metro area also saw several days of hazy skies and elevated particulate matter from transported smoke.

Residents of north-central Idaho near the Lochsa River fires have experienced degraded air quality, with smoke pooling in valleys during calm overnight periods. Improving airflow and precipitation are expected to reduce these impacts as the week progresses.

Health Protective Actions

Public health officials and the Oregon DEQ recommend the following when smoke is present in your area:

  • Limit time outdoors, especially strenuous outdoor activity.
  • Keep windows and doors closed when outdoor smoke is heavy.
  • Use air purifiers with HEPA filters indoors if available.
  • Wear a properly fitted N95 or P100 respirator if you must be outside during heavy smoke events.
  • Check AirNow.gov or the Oregon Smoke Information blog (oregonsmoke.org) for current conditions.
  • Sensitive groups — including children, the elderly, and people with heart or lung conditions — should be especially cautious even during moderate smoke events.

Looking Ahead

The National Weather Service forecast indicates the improving air quality is tied to a broader cooling trend moving through the region. Overnight lows dropping into the 40s across many elevated areas, combined with increased moisture, should continue to help settle smoke and reduce active fire behavior on large fires. However, meteorologists caution that any return to hot, dry, and windy conditions could rapidly reverse air quality gains if fires re-intensify.

Residents are encouraged to continue monitoring AirNow.gov, the Oregon DEQ smoke blog at oregonsmoke.org, and local National Weather Service forecast offices for the latest air quality and fire weather information throughout the remainder of the fire season.