Fire Weather Outlook: Autumn Transition Brings Mixed Signals Across the Pacific Northwest

A pattern shift is underway across the Pacific Northwest as October approaches, with cooler and wetter conditions moving into the region after one of the most severe fire weather summers on record. But fire weather specialists caution that the transition is uneven and that vulnerable areas — particularly in eastern Oregon, the Columbia Basin, and portions of Idaho — could still see dangerous fire conditions through mid-October.

What the Forecasts Show

The National Weather Service issued its September 25 fire weather summary describing conditions across the country. For the Pacific Northwest, the news is largely positive:

Widespread showers and rainfall are occurring near and west of the Cascades in Oregon and Washington
Wetting rain — enough to substantially increase fuel moisture — is expected in northern Idaho and western Montana
The Columbia Basin is seeing breezy west winds, but relative humidity values are remaining above 30% — a significant improvement over the critically low values that drove August's catastrophic fire behavior
Isolated to scattered showers are expected across the broader region

These conditions are encouraging for fire managers working to achieve containment on lingering incidents and for crews conducting mop-up operations on large fires that burned through the summer.

Where Risk Remains

Not all of the region is getting equal relief. Fire weather specialists from the Northwest Coordination Center note that the Great Basin — which extends into southeastern Oregon and southern Idaho — continues to see warm and dry conditions that can support fire growth. While winds are expected to be light in much of this area, the combination of dry fuels and low humidity means that any ignitions would have the potential to spread.

Similarly, the National Weather Service is tracking areas of elevated conditions — relative humidity from 10% to 20% — stretching from northern Nevada into central Montana, including portions of the eastern Great Basin that border the Pacific Northwest. Firefighters remain vigilant in these areas despite the overall reduction in fire activity.

What Drove This Summer’s Extreme Fire Weather

The 2026 fire season in the Pacific Northwest was defined by a series of exceptional weather events, most notably the early August Particularly Dangerous Situation (PDS) Red Flag Warning that produced conditions fire meteorologists described as unprecedented for eastern Washington and Oregon. That event combined record heat, wind gusts in the 40-60 mph range, and relative humidity values in the single digits across a broad area — conditions that allowed fires to grow at rates that made suppression nearly impossible in the first hours of ignition.

Earlier in the season, a significant Red Flag Warning event east of the Cascades led to substantial expansion of existing fires in eastern Oregon and Washington and contributed directly to three new large fires near Spokane. The NIFC September outlook noted that this weather pattern "led to substantial expansion on existing fires in eastern Oregon and Washington and contributed to three new large fires near Spokane, Washington, which together damaged or destroyed more than 800 structures within the city."

Fuel Conditions Heading Into October

Despite the improving weather, fuel conditions across much of the Pacific Northwest remain critically dry from a summer of record heat and drought. Soil moisture deficits, low live fuel moisture values in shrublands, and abundant fine dead fuels — grasses and annual plants cured by months of heat — mean that fire can still spread under the right weather window.

Fire danger ratings in most of eastern Oregon and Washington remain in the "High" to "Very High" range, and some interior valleys and rain-shadow areas on the east slopes of the Cascades could see "Extreme" fire danger if warm, dry, and windy conditions return in October. The transition season is historically marked by periodic dry offshore flow events that can bring dangerous fire weather even after autumn moisture has arrived.

Recommendations for the Public

Continue to avoid outdoor burning even as Washington’s statewide ban expires — local conditions may still warrant caution
Watch for National Weather Service Red Flag Warnings and fire weather watches through mid-October
Keep defensible space clear of flammable materials around structures
Sign up for county-level emergency alerts to receive timely evacuation notifications
Report any smoke or fire sightings to 911 immediately