Washington Wildfire Roundup: Sinlahekin Tops 166,000 Acres Among 13 Large Fires Burning Statewide

Washington state is battling 13 large wildfires as of September 5, 2026, with blazes stretching from the Cascade Range to the Okanogan Highlands and the North Cascades. The fires represent one of the most active periods in the state's recent history, coming on the heels of extreme fire weather that struck eastern Washington in late July and early August.

Sinlahekin Fire: Largest Active Blaze in Washington

The Sinlahekin Fire, burning approximately 12 miles west of Tonasket in Okanogan County, has scorched 166,373 acres and stands at just 39 percent containment — making it the largest currently active fire in the state. The fire has driven evacuations in the Sinlahekin Valley and threatened communities in a region that has seen repeated large fires over the past decade. Crews are working in challenging terrain with an emphasis on structure protection and establishing containment lines along ridges.

Ptarmigan Fire

The Ptarmigan Fire, burning about 20 miles northwest of Mazama in the Methow Valley, has reached 25,166 acres with 73 percent containment as of September 5. Firefighting progress has accelerated in recent days with the arrival of cooler, more humid conditions. Crews are focused on securing the fire’s perimeter to prevent any reactivation as weather patterns remain favorable.

Sisi Fire: Remote North Cascades Blaze

The Sisi Fire, burning approximately 10 miles northwest of Stehekin in the Lake Chelan area, has grown to approximately 2,104 acres with zero percent containment. The fire’s remote location in the Chelan-Okanogan wilderness makes ground access extremely difficult. Crews reported moderated fire behavior following scattered precipitation in recent days and are working on perimeter control. A Complex Incident Management Team (CIMT) is currently managing the Sisi incident.

North Cascades and Cascade Foothills

Several fires continue burning along and near the Cascades:

The Border 2 Fire in North Cascades National Park, 20 miles northeast of Marblemount, has burned 8,043 acres and is 72 percent contained.
The Electric Fire on the Mt. Baker-Snoqualmie National Forest, 7 miles north of Marblemount, has burned 622 acres with 24 percent containment.
The King Fire on the Okanogan-Wenatchee National Forest, 7 miles northeast of Snoqualmie Pass, has burned 2,991 acres with 0 percent containment.
The Goat Fire on the Okanogan-Wenatchee National Forest, 15 miles north of Ronald, has burned 794 acres with 0 percent containment.
The High Lava Fire on the Gifford Pinchot National Forest, 11 miles northwest of Stabler, has burned 2,899 acres with 63 percent containment.

Improving Weather Bringing Relief

The arrival of cooler temperatures and spotty precipitation across the Pacific Northwest has reduced fire weather threat levels significantly. Fire managers expect continued progress on most Washington fires through the coming week, though the Sinlahekin Fire’s large size and active perimeter will require sustained resources to fully contain.