"This fire is notable for its steady containment progress despite a relatively large acreage and the deployment of up to 166 personnel, reflecting significant resource commitment by the U.S. Forest Service."
The North Fork Lost Horse wildfire, located 10 miles northwest of Darby in Ravalli County, Montana, was first reported on August 6, 2026, after a natural ignition. The fire has burned 118 acres and is currently 70% contained, with minimal fire behavior described as creeping, smoldering, and backing. Over the course of the timeline, containment rose from 0% on the first report to 70% by mid‑August, while personnel numbers fluctuated from 81 to a peak of 166 before dropping to 3 in the latest update. The incident remains under the jurisdiction of the U.S. Forest Service, and the estimated cost has risen to $4,754,584 as of September 3, 2026.
Official source description: 10 Miles NW from Darby, MT
Minimal; Smoldering; Backing
Good air quality. Outdoor activity is generally safe near this incident.
Nearest reporting station: Hamilton. Source: AirNow.gov (EPA).
The fire is currently minimal in behavior and 70% contained; however, residents should remain vigilant for potential flare‑ups and follow any local advisories.
IRWIN ID: {4E04440D-FEA1-4FC8-B961-F35F1D3BDF42}
Discovered: Jul 25, 2026
Cause: Natural
Managing Agency: USFS
Est. Cost to Date: $4,754,584
Coordinates: 46.162, -114.337
Other wildfires that have recently been contained or dropped from official tracking in MT.
The North Fork Lost Horse Fire has burned 118 acres as of September 3, 2026.
As of the latest update, the North Fork Lost Horse Fire is 70% contained.
The official cause has been listed as: Natural.
The North Fork Lost Horse Fire is burning in Ravalli, MT.
Yes, as of the latest official update, the North Fork Lost Horse Fire remains active.
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