Santa Rosa & Northern California Fire Cause: How Did the Fires Spread So Fast?

The Santa Rosa and other Northern California fires in Napa and Sonoma County are spreading fast and leaving destruction in their wake. So far, 10 people have died and at least 1,500 homes and businesses have been destroyed from a total of 15 fires in eight counties. More than 20,000 people have been evacuated. Fifteen fires burned more than 73,000 acres since Sunday night.

But what caused the fires? And why are they spreading so fast?

An exact cause of the Santa Rosa fire and the other northern California fires isn’t yet known. Officials haven’t said if they were created by natural causes or man-made. But they do have an idea why the fires grew so quickly.

The Tubbs fire near Santa Rosa had already burned more than 35,000 acres as of Monday morning. But the fire itself began around 10 p.m. Sunday night.

The biggest of the fires began near Highway 128 in Napa County, moving toward Santa Rosa on Sunday night, ABC 7 reported.

The fires in Napa and Sonoma counties grew so fast and have been so devastating because they started during extremely dry and windy conditions. On the ridgetops, some gusts — called Diablo winds — reached as high as 70 mph, the LA Times reported. Low humidity and warmer temperatures also helped the fires spread.

One native told the LA Times that although fires in the mountains weren’t uncommon this time of year, nothing to this extent had happened in Santa Rosa before.

Napa County, meanwhile, is dealing with three fires. One threatened 10,000 acres in northern Napa County, one threatened 8,000 acres, and a third affected 2,000 acres.

We will update this story if more details become available about the exact cause of the northern California fires.