West Fork Fire

201561,723 acresAlaska

The West Fork Fire burned 61,723 acres, about 96 square miles, across Yukon-Koyukuk Census Area. It began on June 20, 2015.

Watch how it happened

West Fork Fire · 2015

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
Detections4,528satellite fire pixels

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 West Fork Fire
Burn severity by class
SeverityShareAcres
Highmost vegetation consumed, soils altered18%11,313
Moderatemixed: many trees killed, some survive37%23,139
Lowsurface fire, most trees survive24%15,040
Unburned to lowislands inside the perimeter, little change12%7,479
Not mappedcloud, shadow or water in the satellite images7.7%4,748

18% of the area inside the perimeter burned at high severity, about 11,313 acres; 56% 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
Yukon-Koyukuk Census AreaAK61,750

Other large fires in Alaska in 2015

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