Megafires of the Last Decade

The 50 largest named US wildfires of the last 10 years, ranked by acres burned.

What counts as a megafire? There is no single official definition, but the term is generally used for wildfires that burn over 100,000 acres. A handful of fires each year now exceed 250,000 acres, and a few have crossed 1 million acres — the 2020 August Complex in California hit 1,032,648 acres, the first confirmed "gigafire" in modern US records. These extreme-scale fires result from a combination of climate-driven fuel drying, accumulated fuel loads from decades of fire suppression, longer fire seasons, and overlapping ignitions during extreme weather events like the lightning siege of August 2020.

Rank Fire Name State Year Acres Burned Structures Cause
No megafire data available.

Why megafires are getting bigger

  • Longer fire seasons — earlier snowmelt, later first autumn rains
  • Accumulated fuels from a century of aggressive fire suppression
  • Hotter, drier summers and more intense droughts
  • Overlapping ignitions during lightning outbreaks exceed suppression capacity
  • Wildland-Urban Interface expansion puts more structures in harm's way