Now California Wildfires Burn All Year 

(Bloomberg) -- California’s wildfire season used to last a few months. Now the state burns all year.

Global warming has intensified California’s cyclical droughts, leaving the land riddled with pockets of dry brush that persist even amid winter rains. That became clear last week when a blaze broke out 300 miles (480 kilometers) north of San Francisco, burning 30 acres in Humboldt County.

The notion that fires are no longer seasonal looms large as PG&E Corp. prepares to file for bankruptcy in the face of $30 billion in potential liabilities from blazes in 2017 and 2018. Historically, PG&E and other California utilities only needed to worry about fire in late summer and fall. Now they’re perpetually exposed to the risk that power lines could spark an inferno.

“Humboldt County is supposed to be dripping wet this time of year,” said Scott McLean, spokesman for the California Department of Forestry & Fire Protection. “Climate is consistently against us.”

Now California Wildfires Burn All Year 

The never-ending fire season stems largely from a years-long drought that gripped much of California before easing in 2017. An estimated 129 million trees died from a lack of nutrients and infestations from bark beetles, leaving hillsides and forests dappled with kindling.

The results have been grim. Record-setting fires have swept across the state, killing more than 100 people in two years. Last year included the deadliest and largest blazes in state history. All told, nearly 900,000 acres (360,000 hectares) burned in 2018 on land Cal Fire patrols. That’s more than triple the five-year average.

Now California Wildfires Burn All Year 

When rains do come, they haven’t been enough to fully revive the landscape. Paradoxically, the water also becomes a catalyst for more fires. As it splashes onto hills and valleys left barren by years of drought, the rain leads to a flurry of grass and brush. Unfortunately, there isn’t enough precipitation during the California summer to keep them moist and supple. So they wither and become tinder.

In 2018, this played out across the state. Temperatures hit 100 degrees Fahrenheit (38 Celsius) in June and stayed there. The city of Redding was 100 degrees or more 51 times from June to September.

“The grass dried out so fast,” McLean said. “The large fires had receptive fuels. Then you had another one before the first one was finished. Then you had another one on top of that, and another one on top of that.”

Winter Storms

Now in the midst of its wet season, winter storms have already brought California almost half the water state officials like to have when the dry season starts in April, said Chris Orrock, a spokesman for the California Department of Water Resources. Snowpack in the mountains, akin to water in the bank, is running ahead of last year in many places.

A Pacific storm coming ashore this week is forecast to dump as much as 6 inches of rain across Southern California, potentially causing floods and mudslides near Los Angeles in areas where brush burned away during wildfires. Snow will fall by the foot in the Sierra Nevada mountains, said Richard Otto, a forecaster at the U.S. Weather Prediction Center in College Park, Maryland.

“It will be a good soaking all around,” Otto said.

After the storm passes, the state is forecast to be drier for a time. That could mean more fires like the one in Humboldt County last week.

©2019 Bloomberg L.P.