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MegafireCalifornia · 2020

August Complex (2020)

August 17 – November 12, 2020

Acres burned
1,032,648
Deaths
1
Structures destroyed
935
Damage
$280M

Fast Facts

Date
August 17 – November 12, 2020
Acres burned
1,032,648 — largest single wildfire in CA history
Counties
Mendocino, Tehama, Glenn, Lake, Colusa, Trinity, Shasta
Origin
38 lightning-caused ignitions that merged
Deaths
1
Structures destroyed
935
Rank
First "gigafire" (>1M acres) in modern California

Cause: Lightning storm — 38 separate ignitions, later merged

Perimeter & Origin Map

Hover or tap markers for details
Ignition point
Impact location
Burn perimeter
Severity: > 100,000 acres

Perimeter is a simplified polygon approximating the final burn footprint from NIFC/CalFire records. Origin coordinates from the official incident investigation report.

The 2020 lightning siege

Between August 16 and 19, 2020, an unusually dry mid-level moisture plume crossed Northern California from the south, generating a historic lightning siege that produced approximately 12,000 cloud-to-ground strikes. The strikes ignited an estimated 650 wildfires statewide. Initial-attack resources — already thin from earlier season activity — were overwhelmed. In the Mendocino National Forest, 38 separate ignitions occurred over those three days. The US Forest Service initially managed them as individual incidents but progressively combined them into complexes as merged. By late August the combined incident, then known as the "Doe Fire," covered over 300,000 acres. As additional smaller fires merged, the incident was renamed the August Complex on September 9, 2020.

The first gigafire

By early October 2020, the August Complex had grown beyond 800,000 acres. Sustained dry, warm weather and chronic understaffing of suppression resources allowed the fire to continue expanding even as resources from across the West were committed. On October 5, the incident crossed the one-million-acre threshold — the first time a single wildfire in California's recorded history had done so, and the first conifer-forest fire in the Lower 48 to reach that scale. Containment was finally declared on November 12, 2020, after autumn rain and cooler temperatures stopped further spread. The incident burned at relatively low intensity in much of its footprint (it largely traversed remote, low-population terrain) and produced only one direct fatality (a firefighter killed when a tree fell on his vehicle), but it permanently changed the operational vocabulary of US wildfire response by introducing the concept of routine million-acre incidents.

Frequently Asked Questions

How big was the August Complex fire?

The August Complex burned 1,032,648 acres (approximately 1,614 square miles) across seven counties in northern California — making it the largest single wildfire in California's recorded history. It was the first wildfire in the modern era to exceed one million acres in a single state, sometimes called a "gigafire."

How did the August Complex start?

The August Complex began as 38 separate ignitions across the Mendocino National Forest during a historic lightning siege from August 16-19, 2020. As initial-attack resources were overwhelmed by simultaneous fires across northern California (the LNU and SCU complexes were burning in parallel further south), many of the smaller Mendocino fires merged into what was first managed as the "Doe Fire" and later renamed the August Complex.

Why was the August Complex called a "gigafire"?

The term "gigafire" had been used informally by fire researchers since the early 2010s to describe wildfires exceeding one million acres — a scale previously associated only with rangeland fires in remote Alaska or the Australian outback. The August Complex was the first wildfire in modern California history to reach the gigafire threshold, and the first conifer-forest fire in the Lower 48 to do so.

Sources

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