Smoke from dozens of active wildfires burning across Oregon, Washington, and Idaho has pushed air quality into the unhealthy and hazardous range across large portions of the Pacific Northwest, with official advisories in place for more than a dozen Oregon counties and ten Idaho counties. Health officials are urging residents — particularly those with respiratory conditions — to limit outdoor exposure and take protective measures.

Oregon Air Quality Advisory

The Oregon Department of Environmental Quality (DEQ) issued an air quality advisory beginning Monday, July 27, covering a wide swath of eastern and central Oregon. As of August 1, the advisory remains in effect and is expected to last at least through Monday, August 3. Counties under advisory include:

  • Baker, Crook, Gilliam, Grant, Harney, Jefferson, Malheur (northern), Morrow, Umatilla (eastern), Union, Wallowa, Wasco (southern), and Wheeler counties

Intermittent smoke is also affecting northern Klamath, Lake, and southern Malheur counties. Areas of Harney and Malheur counties have recorded readings in the "Very Unhealthy" range, with particulate concentrations exceeding 200 on the Air Quality Index (AQI).

Idaho Advisory

The Idaho Department of Environmental Quality has issued a separate air quality advisory covering ten counties in southwestern and central Idaho, including Ada, Adams, Boise, Canyon, Elmore, Gem, Owyhee, Payette, Valley, and Washington counties. The Big Grass Fire in Owyhee County is the primary driver of smoke in Idaho, with conditions reaching "Unhealthy" to "Very Unhealthy" levels.

How Far Smoke Has Traveled

Northwest wildfire smoke has traveled well beyond state borders. Thick plumes have reached as far east as North Dakota, and satellite imagery confirms a smoke blanket covering significant portions of the Intermountain West. NASA imagery captured a continuous smoke plume extending hundreds of miles from the largest Oregon fires, including the Hay Creek Complex, Big Grass, Akawa Butte, and Powder River fires.

Health Guidance

The Oregon DEQ and Idaho DEQ recommend the following protective steps during smoke events:

  • Stay indoors: Keep windows and doors closed. Run air conditioning on recirculate mode, not fresh air intake.
  • Use air filtration: HEPA air purifiers can significantly reduce indoor particulate levels. DIY box fan filtration units with MERV-13 or better filters are an effective low-cost alternative.
  • Avoid strenuous activity outdoors: Even brief periods of hard exertion in smoky conditions can cause significant health impacts.
  • Check AQI before going out: Use AirNow.gov or the Oregon Smoke Information website (oregonsmoke.org) for up-to-date local conditions.
  • Wear a properly fitted N95 or KN95 mask if you must be outdoors for extended periods.
  • People at highest risk include children, the elderly, pregnant women, and anyone with heart or lung disease — they should take extra precautions or consider temporarily relocating to areas with cleaner air.

Conditions can shift rapidly depending on wind direction. Monitor advisories closely, especially with the forecast wind event Saturday afternoon, which may temporarily improve smoke conditions in some areas while spreading smoke to new locations.