California’s Fire Season, Explained

When is fire season in California?

As the climate crisis intensifies, California faces the risk of wildfires all year now, particularly in years of extreme drought conditions that leave the state's foliage a tinderbox.

Most fires happen between the months of April and October, as weather becomes warmer and drier. In Southern California in particular, the hot and dry Santa Ana winds increase wildfire risk in October and November.

Some of the worst wildfires in California history occurred outside that window. The Camp Fire in 2018, which killed 85 and destroyed the town of Paradise outside Redding in Northern California, was a November fire.

How large have wildfires been over time?

Mega-droughts and rising temperatures aggravated by climate change have increased the frequency and intensity of California wildfires in recent years.

As of 2022, half of the state's 20 largest fires had occurred over the previous five years. Of those, seven occurred in 2020 and 2021. All but two of the state's largest fires occurred in the 21st century.

Three major blazes ignited by lightning strikes in August 2020 made that year one of the worst on record for total acres burned. At least 4.3 million acres burned, blanketing large parts of California with toxic smoke for weeks.

What causes California’s wildfires?

Arson and power lines are the major triggers. A 2022 audit showed that utilities aren’t doing enough to prevent fires. But lightning-sparked fires, like the one that burned Big Basin park, are a fairly recent trend.

Unpredictable and hugely powerful lightning storms — tens of thousands of strikes in a span of days — bombard already dry and vulnerable landscapes. Scientists say to expect more lightning as the planet warms. And, aided and abetted by drought, more than 163 million trees have been killed by drought or insects.

How has the increasing severity of California wildfires impacted the state?

The job of battling these larger, more stubborn California wildfires has become more complicated, fearsome and deadly, straining the state’s already overworked firefighters.

And much, much more costly. The Legislative Analyst’s Office provided this sobering calculation: CalFire’s total funding for fire protection, resource management and fire prevention has grown from $800 million in 2005-06 to an estimated $3.7 billion in 2021-22.

As the impacts and costs surge, homeowners are still finding that insurance companies are canceling their policies — even if they fire-harden their property.

More attention is being paid to the unhealthy smoke lingering in communities. Even California’s crops are harmed, with concerns about a smoke- tainted grape harvest and impacting the state’s $58 billion wine industry.

Scientists and fire bosses are moving away from all-out suppression of every fire to understanding that fire can be harnessed as a tool. The benefits of fire, long part of the culture of native Californians, are now part of the state’s planning.

After all, California’s landscape evolved with fire. What remains is for its inhabitants to adapt to the new reality.

And that requires yet another new term: Welcome to the “Pyrocene,” coined by fire scientist Stephen J.Pyne. The age of fire.