Lolo Peak Fire

201762,337 acresIdaho and Montana

The Lolo Peak Fire burned 62,337 acres, about 97 square miles, across 3 counties. It began on July 15, 2017.

Watch how it happened

Lolo Peak Fire · 2017

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

Detections5,859satellite 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 (4,896 VIIRS and 963 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 Lolo Peak Fire

Burn severity by class
Severity	Share	Acres
Highmost vegetation consumed, soils altered	18%	11,099
Moderatemixed: many trees killed, some survive	25%	15,855
Lowsurface fire, most trees survive	32%	19,741
Unburned to lowislands inside the perimeter, little change	25%	15,535
Increased greennessvegetation greener after the fire than before	0.2%	100

18% of the area inside the perimeter burned at high severity, about 11,099 acres; 43% 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

Missoula County	MT	42,054
Ravalli County	MT	18,945
Idaho County	ID	1,316

Other large fires in Idaho and Montana in 2017

Bridge Coulee Fire222,645 acres
Rice Ridge Fire171,675 acres
Highline Fire93,679 acres
Sartin Draw Fire91,520 acres
Deer Creek Fire90,111 acres
Meyers Fire68,734 acres
Powerline Fire54,349 acres
Mammoth Cave Fire50,410 acres

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