Pacific Northwest Air Quality Rebounds as Fire Season Wraps — What to Expect This Winter

After a summer and fall marked by recurring smoke events, Pacific Northwest residents can breathe easier as the 2026 fire season approaches its close. With active fires in Oregon and Washington largely contained or transitioning to winter management, regional air quality has improved significantly from the hazardous conditions experienced at the seasons peak.

The Smoke Season Behind Us

The 2026 fire season brought multiple significant smoke events to the Pacific Northwest, driven by 38 large fires across Oregon, Washington, and Idaho at peak activity. Smoke from fires including the Little Giant Fire (172,912 acres in Washington), the Three Queens Fire near Snoqualmie Pass, and Oregons Grasshopper Fire (93,971 acres near Dufur) degraded air quality across wide swaths of the region for extended periods.

At its worst, the Oregon Department of Environmental Quality issued air quality advisories for northern Crook, Jefferson, and southern Wasco counties, where sustained smoke from multiple fires created unhealthy conditions. Seattle, Portland, Bend, and other urban areas saw repeated Air Quality Index (AQI) spikes into Unhealthy and Very Unhealthy categories during peak burning periods.

Where Things Stand Now

As of early November 2026, fire activity across the Pacific Northwest has dramatically declined:

The Austin Fire on Mt. Hood National Forest is 98% contained at 12,888 acres
The Three Queens Fire closure has been reduced, with evacuation orders lifted
The Sisi Fire in the North Cascades continues to smolder but shows minimal active behavior under snow and cloud cover
The National Preparedness Level has fallen to 1, the lowest level

A storm system expected to bring rain to the Cascades and mountain snow through November 4–7 will further extinguish residual burning across the region.

Winter Burning and Indoor Air Quality

As outdoor wildfire smoke diminishes, winter introduces a different air quality challenge. Wood stoves, fireplaces, and biomass burning increase sharply in cold months, contributing fine particle pollution (PM2.5) to valleys and basins — particularly during temperature inversions, when cold dense air traps smoke at ground level.

Oregon and Washington air agencies issue periodic Burn Bans and No-Burn days during inversions. Residents with wood-burning appliances are encouraged to:

Burn only dry, seasoned hardwood — never green wood, garbage, or treated lumber
Have chimneys professionally cleaned and inspected before the heating season
Check local AQI forecasts at AirNow (airnow.gov) before lighting fires
Comply with Burn Bans and No-Burn advisories issued by local clean air agencies

Lingering Health Effects from a Severe Season

Health officials note that cumulative smoke exposure from an extreme fire season can have effects that persist beyond the fire season itself. Repeated exposure to wildfire smoke PM2.5 is associated with respiratory and cardiovascular impacts. Individuals with asthma, COPD, heart disease, or other conditions are advised to continue monitoring air quality and to consult a healthcare provider if symptoms persist into winter.

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