Trail Creek Fire

202162,475 acresIdaho and Montana

The Trail Creek Fire burned 62,475 acres, about 98 square miles, across 2 counties. It began on July 8, 2021.

Watch how it happened

Trail Creek Fire · 2021

How it happened

Watch it burn in the order satellites saw it, coloured by how severely each place burned.

About this replay

Date (UTC)—Historical replay

Burned so far—acres

High severity—of the area so far

Detections5,088satellite fire pixels

Fire milestones

Burn severityHigh, Moderate, Low, Unburned to low, Increased greenness

Burning nowAreas reached in the last half day of satellite passes

Washington, D.C., to scale61 square miles of land, drawn at the fire’s scale

Timing: NASA FIRMS satellite fire detections (4,237 VIIRS and 851 MODIS) inside the final perimeter; each place takes the time of its nearest detection, so the order is satellite-observed but interpolated between passes, roughly every 12 hours. Severity: Monitoring Trends in Burn Severity (USGS, U.S. Forest Service), mapped from Landsat after the fire.

How severely it burned

Burn severity inside the final perimeter, classified from Landsat images taken before and after the fire.

Map of burn severity across the Trail Creek Fire

Burn severity by class
Severity	Share	Acres
Highmost vegetation consumed, soils altered	26%	16,180
Moderatemixed: many trees killed, some survive	25%	15,525
Lowsurface fire, most trees survive	32%	20,022
Unburned to lowislands inside the perimeter, little change	17%	10,669
Increased greennessvegetation greener after the fire than before	0.1%	79

26% of the area inside the perimeter burned at high severity, about 16,180 acres; 51% burned at moderate or high severity.

Monitoring Trends in Burn Severity (U.S. Geological Survey and USDA Forest Service). Classes come from the change in a Landsat burn index (dNBR) between images before and after the fire; acres are each class’s share of the fire’s mapped area.

Where it burned

Acres inside each county, measured from the satellite-mapped perimeter.

Acres burned by county

Beaverhead County	MT	51,827
Lemhi County	ID	10,602

Other large fires in Idaho and Montana in 2021

Richard Spring Fire168,686 acres
Shovel Creek Fire109,743 acres
Boundary Fire97,976 acres
P F Fire66,446 acres
Woods Creek Fire55,808 acres
Dixie Fire45,239 acres
Thorne Creek Fire39,680 acres
Alder Creek Fire38,181 acres

Monitoring Trends in Burn Severity (USGS and U.S. Forest Service). Type recorded: Wildfire.