SISI

Rain slows fire spread as crews maintain protection lines near Stehekin

The Sisi Fire is burning in steep, remote terrain within the Okanogan-Wenatchee National Forest and North Cascades National Park, with backing fire activity in the Cabin Creek and Moon Creek drainages. Recent rainfall and higher humidity have moderated overall fire spread to creeping and smoldering, though water drops were used to check northern perimeter movement toward the Stehekin River. Crews have completed structure protection preparations around Stehekin and continue strengthening community defense lines.

Evacuations and Closures

• September 4: North Cascades National Park closed Stehekin Valley Road from Stehekin Valley Ranch to High Bridge, the High Bridge area, the Battalion Cross-country Zone, and Shady, Tumwater, High Bridge, and Heaton campgrounds.
• September 4: North Cascades National Park closed the Agnes Gorge Trail, Bullion Loop Trail, McGregor Mountain Trail, Company Creek Trail to the park boundary, and the Pacific Crest Trail from the park boundary to Bridge Creek Camp.
• September 6: Chelan Ranger District maintains trail closures and a forest-wide campfire ban, while closure orders were reduced in parts of the Wenatchee River and Entiat Ranger Districts.
• September 4: Chelan County emergency officials advise residents near Stehekin to monitor current evacuation status on the county's interactive emergency map.
• September 4: A Temporary Flight Restriction remains in effect over the fire area.

Impact

Increased traffic from arriving fire personnel and heavy equipment is affecting local roads in Stehekin, prompting officials to urge caution for motorists and pedestrians. No structural losses or injuries have been reported.

Conditions and Outlook

Overcast skies will give way to fair weather over the coming days, bringing gradually warmer afternoons, lower humidity, and light northwest winds shifting westerly with minimal chance of precipitation. Fire activity is expected to remain largely creeping and smoldering in heavy dead and down fuels, though drying conditions could stir heat in sheltered pockets. Crews plan to patrol community lines and maintain structure protection systems in the Stehekin Valley.

Cause and Context

Lightning ignited the fire on August 14, 2026, in steep wilderness roughly ten miles northwest of Stehekin. Northwest Incident Management Team 12 is directing operations in coordination with the Little Giant Fire.

Resources

• Sisi Fire InciWeb Incident Page
• North Cascades National Park Fire Closures

Official updates current through September 7, 2026.