Fire weather conditions across the Pacific Northwest have reached levels not seen since 2020, with the National Weather Service issuing its highest-tier fire weather alerts — Particularly Dangerous Situation (PDS) Red Flag Warnings — for large portions of eastern Washington and northeastern Oregon. The warnings signal an elevated threat of rapid, erratic, and potentially uncontrollable fire spread.

What Is a PDS Red Flag Warning?

A standard Red Flag Warning is issued when conditions are favorable for extreme fire behavior. A Particularly Dangerous Situation (PDS) qualifier is added only when meteorologists believe those conditions are exceptional — that fire behavior will likely be beyond the suppression capabilities of firefighting resources and that extreme fire spread is highly probable. PDS Red Flag Warnings are rare; the Pacific Northwest had not seen one since September 2020, when multiple devastating fires burned across Oregon and Washington.

The Weather Setup

The catalyst for this week's extreme fire weather was a dry cold front that moved across the region starting around August 1-2. Rather than bringing meaningful precipitation, the front delivered strong gusty winds with gusts of 40 to 55 mph across eastern Washington, the Columbia Basin, and northeastern Oregon. Combined with daytime temperatures approaching 100°F in the Willamette Valley and even higher in the Columbia Basin, and relative humidity values plummeting to 4-10 percent across the Sierra Front and Columbia Plateau, the front created a nearly ideal ignition and spread environment.

The National Weather Service in Pendleton issued PDS Red Flag Warnings covering portions of eastern Washington and northeastern Oregon — areas already hosting dozens of active large fires. The NWS in Spokane issued complementary warnings for north-central and eastern Washington.

Wind Events and Fire Runs

The consequences of the fire weather were immediate and severe. The wind event that coincided with the PDS warnings drove the catastrophic spread of the Spokane area fires on August 1-2, during which the Old Trails Fire and several companion fires tore through residential neighborhoods in Spokane's west side. The same wind event pushed the Tartar Fire an estimated 20 miles toward Weiser, Idaho, and drove dramatic growth on the Sinlahekin Fire in Okanogan County.

In the Columbia River Gorge, locally gusty east winds of up to 30 mph were recorded during morning hours, creating extreme fire spread potential along the Oregon-Washington border corridor.

The Ongoing Fuel Situation

Meteorologists and fire behavior analysts point to fuel conditions as the underlying driver of why wind events this year are so destructive. An extended drought has left fine fuels — grasses, sagebrush, and light timber — at critically low moisture levels across eastern Oregon, eastern Washington, and southern Idaho. The NIFC Predictive Services August outlook notes that the entire northwestern United States is forecast to experience above-normal fire potential through the remainder of the month.

Live fuel moisture measurements in many drainages across eastern Oregon and Washington are at or below the fifth percentile historically — meaning fuels are drier than 95 percent of all recorded measurements for this time of year. Dead fuel moisture in 100-hour fuels is similarly extreme in many locations.

What Forecasters Are Watching

The National Weather Service and NIFC Predictive Services are closely monitoring several potential weather scenarios for the coming weeks:

  • Additional dry cold fronts: Late summer in the Northwest typically features periodic frontal passages that bring wind without meaningful rain — the same setup that drove this week's fires.
  • Offshore flow events: Strong high pressure building over the interior can generate easterly winds that push smoke and hot, dry air into western Oregon and Washington.
  • Possible dry lightning: Isolated dry thunderstorms remain possible on some days, with lightning posing ignition risk without accompanying rain.

The bottom line for residents across eastern Oregon, eastern Washington, and southern Idaho: fire weather conditions remain extreme, and any outdoor burning activities should be suspended. Recreational campfires are banned across much of the region, and residents in fire-prone areas should maintain active evacuation readiness.