Nuns Fire

201756,839 acresCalifornia

The Nuns Fire burned 56,839 acres, about 89 square miles, across 2 counties. It began on October 9, 2017.

Watch how it happened

Nuns 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

Detections2,475satellite 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 (2,002 VIIRS and 473 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 Nuns Fire

Burn severity by class
Severity	Share	Acres
Highmost vegetation consumed, soils altered	10%	5,783
Moderatemixed: many trees killed, some survive	20%	11,451
Lowsurface fire, most trees survive	34%	19,231
Unburned to lowislands inside the perimeter, little change	34%	19,358
Increased greennessvegetation greener after the fire than before	1.6%	913
Not mappedcloud, shadow or water in the satellite images	0.2%	103

10% of the area inside the perimeter burned at high severity, about 5,783 acres; 30% 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

Sonoma County	CA	36,809
Napa County	CA	20,074

Other large fires in California in 2017

Thomas Fire282,076 acres
Oak Fire95,627 acres
Detwiler Fire83,375 acres
Long Valley Fire80,503 acres
Island Fire62,884 acres
Atlas Fire51,629 acres
Steele Fire49,157 acres
Garza Fire48,477 acres

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