Fire weather forecasters at the National Interagency Fire Center are watching a round of Cascade gap winds on Wednesday, September 23, with gusts expected to reach 35 mph through mountain passes including the Columbia River Gorge. The breezy conditions, combined with relative humidity values that have struggled to recover overnight, are keeping fire spread potential elevated across the Pacific Northwest even as the 2026 fire season approaches its traditional close.
Today’s Fire Weather Concern
NIFC’s Wednesday fire weather discussion notes that breezy west winds will develop through Cascade gaps this afternoon, slightly stronger than the previous day. The Columbia Gorge, which historically serves as a powerful wind tunnel between the Columbia Plateau and the Willamette Valley, will see gusts in the 25–35 mph range.
These winds arrive during a period when vegetation across the Pacific Northwest remains critically dry after one of the driest summers on record. Fire managers emphasize that even near-contained fires can experience flare-ups under these conditions, and that unignited fuels in burned areas surrounding active perimeters can still carry fire if wind-driven embers escape containment lines.
Humidity and Overnight Recovery Concerns
Poor overnight humidity recovery has been an ongoing challenge throughout September in the Pacific Northwest. When relative humidity fails to rebound during overnight hours, fuels remain preheated and dry heading into the next day’s heating cycle—accelerating fire weather concerns even in the absence of extreme afternoon temperatures. Northern California is experiencing the most critical conditions nationally, with relative humidity dropping to 10–20% and breezy winds driving significant fire potential there.
What to Watch in the Northwest
Fire weather watches and red flag conditions have been issued across portions of the region multiple times this month. Earlier in September, red flag warnings covered large portions of eastern Oregon fire weather zones including Burns BLM, Steens Mountain, Northwestern Vale BLM, and Baker Valley, driven by low humidity and gusty winds associated with passing weather systems.
Idaho saw red flag warnings for the Northern and Southern Boise National Forest and Camas Prairie zone in the third week of September, with concerns about dry lightning from isolated convective storms—a pattern that has sparked numerous fires across the Great Basin throughout the season.
Looking Ahead: Fall Relief on the Horizon
The longer-range outlook holds some relief. September’s final week typically marks the beginning of the Pacific Northwest’s transition to fall precipitation patterns, with the jet stream repositioning to bring more frequent frontal systems off the Pacific. Wet thunderstorms are already delivering meaningful rainfall to eastern Montana and Wyoming, and similar moisture is expected to eventually reach the Pacific Northwest.
However, fire managers and residents should not assume the season is over. Stage 1 fire restrictions remain in effect on federal lands across central Oregon, and Washington’s active large fires—including the Three Queens Fire near Snoqualmie Pass at just 23% containment—remain highly susceptible to any wind event that could breach existing containment lines.
Until official closures and restrictions are lifted, the public is asked to follow all fire prevention guidelines, avoid debris burning, and report new smoke or fire immediately to 911.