Sinlahekin Fire Becomes State’s Largest This Year At 141,000+ Acres, Now 42% Contained

Firefighters in Okanogan County appear to finally be gaining the upper hand on the Sinlahekin Fire, but only after it has enlarged to become Washington's biggest wildfire of the 2026 season.

The blaze was reportedly sparked by lighting about 12 miles west of Tonakset on July 26, and has since grown to an estimated size of 141,411 acres with 42% containment as of Monday (Aug. 10) morning.

Although containment levels have significantly improved since late last week, officials say the fire remains active in several areas, particularly on its western edges, where new evacuations have been issued.

Meanwhile, many evacuations near the blaze's northern and eastern flanks have been downgraded or lifted in recent days.

The fire is known to have destroyed at least two structures, but officials estimate that many others may have been lost, as hundreds remain threatened.

Several local roads, trails, and recreational sites remain closed due to the fire, which is still producing smoke impacts in nearby communities.

Crews will remain active this week making direct attacks on the flames and forging containment lines in some areas.

Thus far, no injuries or fatalities have been attributed to the fire.