Park Fire smoke steers clear of The City — for now

Smoke from the Park Fire has steered clear of The City, but experts warn that doesn’t mean San Franciscans will fully avoid fumes from the blaze that grew into the fifth-largest wildfire in state history Tuesday.

The Park Fire has scorched 383,619 acres — just less than 13 times the size of San Francisco —- across Butte, Plumas, Shasta and Tehama counties in Northern California, as of Cal Fire’s latest update Tuesday morning.

The blaze has destroyed nearly 200 structures, threatened another 4,200, and caused thousands of people to evacuate throughout the region.

The fire ignited in Bidwell Park in Chico a week ago Wednesday due to suspected arson. Ronnie Stout, a 42-year-old Chico resident , was arrested last week for allegedly pushing a burning car into a ravine and setting dry vegetation — that hadn’t burned in decades — ablaze. The fire erupted amid historically hot weather in parts of the area.

Within 72 hours, the Park Fire quadrupled in size to more than 350,000 acres.

“Those three days were just horrific,” Scott Stephens, a wildfire science expert at UC Berkeley, told The Examiner. “The tragedy is that it was an arson fire, which is almost unbelievable to describe.”

Although the fire’s origin is just 170 miles away from The City, the Bay Area’s air quality has remained relatively clean. Juan Romero, a spokesperson for the Bay Area Air Quality Management District, said air quality in the Bay Area has oscillated between good and moderate since the Park Fire sparked.

The Air District issued an air quality advisory on Sunday and Monday due to smoke from the fire , though levels didn’t rise to where it needed to issue a Spare the Air Alert.

The agency said Tuesday that air quality is expected to be “good” in all Bay Area counties through Wednesday.

“At least for the next few days we do not expect smoke impacts [in the Bay Area] as moderate to strong onshore flow will continue to push smoke east and northeastward into Nevada,” Romero said.

Stephens added that is typical for July and August patterns in San Francisco.

“We usually get a lot of southwest winds that go up towards the northeast based on the pressure gradient we have. And we’ve had a lot of those,” he said. “I think potentially, if you get a weather system that would really direct wind in the opposite direction, direct north, you would really have the ability to move smoke our way. We’ve just been really fortunate that it hasn’t happened yet.”

In October 2023, The City experienced its worst air quality since the orange-sky-inducing wildfires of September 2020 amid a series of blazes along the California-Oregon border. Even though those fires were much farther away from The City than the current Park Fire, the wind behavior during that time of year is generally more conducive to smoke wafting into the Bay Area.

But officials cautioned that the lack of wildfire smoke in The City in the last week so far mean San Franciscans should let their guard down. Romero said much of San Francisco’s future air health will depend upon how successful firefighting efforts against the historic blaze are.

Stephens maintained that the Bay Area could “for sure” be affected by Park Fire smoke in the coming days, especially since wind patterns can shift “quickly.”

“If we get something like a high pressure system to our north and something like a low pressure system in Southern California or off the Pacific coast, from high to low, it’s going to move that smoke right to us,” he explained.