On Sunday night, like a desert hurricane, winds heavier than 70 miles per hour whipped Napa Valley, California from the northeast. Then the fires began. Were they the work of an arsonist with a sick sense of timing? Or multiple snapped power lines? We still don’t know the cause, but by night’s end, flames from seventeen new blazes were sweeping down from the hills of wine country and into Bay Area suburbs—Healdsburg, Redwood Valley, and Santa Rosa.
For twelve long hours, the Diablo winds howled. Flames leaped from brush to home, unbeknownst to sleeping families, utterly impossible for firefighters to control. The embers raining down were unquantifiable. “You don’t count the number of raindrops in a downpour,” says Mark Finney, a research forester with the National Forest Service. Every planter box, pine needle, garden, or roof touched by the blizzard of flames ignited. More than 170,000 acres and 3,500 buildings burned overnight. Thousands of residents and visitors evacuated. At least twenty-one people have died. Six hundred and seventy others remain missing. With the winds forecast to return tonight, and increase again in severity this weekend, the disaster rages on.
Just how bad are the Napa fires? “These things aren’t unprecedented at all,” says Finney. True. But for now, these fires have few modern rivals.
October 8, 1871
Day the Peshtigo Fire and the Great Michigan Fire killed 1,600 people and burned 3.8 million acres in Wisconsin and Michigan. That same day, the Great Chicago Fire killed 300 in the Windy City.
Year the Berkeley Hills Fire torched 584 buildings on the backside of the University of California Berkeley. Forty-one years later, Diablo-wind-fanned fires would blacken 83,000 acres in Napa Valley.
Total cost of the 1991 Oakland Hills Fire, which killed 25 and destroyed more than 3,000 homes, the most destructive fire in modern history
Approximate number of structures lost in the 2017 Napa firestorm as of October 11, 2017
Population increase in Napa County since 1980
Increased number of trees on an average Californian acre when compared to 1910, when America started aggressively suppressing wildfires
Estimated number of trees killed by beetles and drought in 2016 alone
Rain that fell on Northern California from October to April. The record rainfall led to the bumper crop of the grass and brush now burning in the fires.
Temperature recorded in San Francisco on September 1—the highest on record
Length of time since Napa Valley’s last wetting rain. Meteorologists say the valley is in a flash drought.
79 miles per hour
Peak winds measured Sunday night. The peak winds during the 1991 firestorm measured 23 miles per hour.
Homes and businesses threatened by the Tubbs Fire, one of 17 currently burning in the state
Number of severe wind events forecast for this weekend
Distance that 60 to 80 mile per hour gusts can throw embers
Days before forecasters see a break in the weather
Correction: This story mistakenly referred to Redwood Valley as Redwood Cities. Outside regrets the error.