Báo cháy rừng California năm 2021

By the end of 2021, a total of 7,396 wildfires burned 2,569,386 acres (1,039,794 ha) across the U.S. state of California. Approximately 3,629 structures were damaged or destroyed by the wildfires, and three firefighters died during the wildfire season.

The wildfire season in California experienced an unusually early start amid an ongoing drought and historically low rainfall and reservoir levels. In January 2021 alone, 297 fires burned 1,171 acres (4.74 km2) on nonfederal land according to the California Department of Forestry and Fire Protection, which is almost triple the number of fires and more than 20 times the acreage of the five-year average for January. The January fires were exacerbated by unseasonably strong Santa Ana winds, and some of them burned in the same areas as previous fires like the CZU Lightning Complex.

Cause the drought was started in early 2020, and fire season in 2021 and drought.

The long term trend is that wildfires in the state are increasing due to climate change in California. The 2021 wildfire season was exceptionally severe in California, although it did not approach the extent of the previous year's wildfire season, which was the largest season in the state's recorded history. By July 11 of that year, more than three times as many acres had burned compared to the previous year, with drought, extreme heat, and reduced snowpack contributing to the severity of the fires. The state also faced an increased risk of post-wildfire landslides.

As of August 18, 2021, the state of California was facing "unprecedented fire conditions" as multiple fires including the Dixie Fire, McFarland Fire, Caldor Fire, and others, raged on. The USDA Forest Service temporarily closed all of California's national forests at the end of August to mitigate the impact of potential fires.

On October 18, 2021, much of the state—particularly Northern California, where the majority of the significant fires had been located—received its first major precipitation since the start of the wildfire season. This significantly lowered wildfire risk in the region.