No one knows yet how it started — A lightning strike? A stove left unattended? A stray spark from a weekend barbecue? — and it’s still unclear when it will end.

But in a matter of hours, the Valley fire had already become the most destructive blaze of a summer marked by catastrophic conflagrations.

Feeding on drought-parched vegetation and whipped by 30 mile per hour winds, the massive wall of flame that began Saturday roared through miles of mountain landscape too fast for containment. Burning so big and so hot it created its own wind conditions, the fire rained ash and embers down on the dense pine forests and neat vineyards of Lake County, Calif., about 100 miles north of San Francisco.

“It wasn’t even a fire. It was like fluorescent evil,” resident Bill Gavin told the Santa Rosa Press-Democrat. “I saw sections like football fields go up in four seconds.”

There was nothing smoke-choked and wildfire-weary fire crews could do to slow its progress, so they focused on getting residents of the rural, mountain-locked valley out of the danger zone. Almost everything that was left behind — cars, pets, beloved homes — became further fuel for the flames.

By Sunday evening, the inferno had ravaged more than 50,000 acres, leaving in its wake thousands of evacuees, hundreds of destroyed homes, two utterly incinerated towns and one life lost, according to the Associated Press.

“It is kind of mind-boggling,” Daniel Swain, a climate scientist at Stanford University, told the Los Angeles Times. “… This fire sort of broke the rules even relative to this incredible season that’s already occurred.”

It is, as the L.A. Times put it, the blaze that California officials have been worried about all summer. Lake County’s dense, drought-dry vegetation made for a fast-moving fire that is difficult to contain, but the area’s many scattered small towns and rural homes made it impossible not to try. The heat wave that scorched much of the state last week only worsened matters.

The fire began on a mountain road near Cobb, Calif. California Department of Forestry and Fire Protection incident chief Todd Derum said it was reported as a structure fire, according to the L.A. Times, but the blaze actually started outside. It’s not clear what provided the initial spark, but it didn’t take long for the fire to spread miles down the mountains and into the nearby communities.

More than 1,000 firefighters from local fire departments on up to the National Guard were called in to battle the conflagration, but it remained zero percent contained Sunday evening. Daniel Berlant, a spokesman for the California Department of Forestry and Fire Protection (Cal Fire), explained that the fire had a frightening ability to hop past firefighters’ containment zones.

“As fire crews would make progress, hold the fire, the fire would burn right past them,” he said in a video news release, adding that winds helped carry embers beyond the leading edge of the flames.

One person has been killed in the fire, Cal Fire spokeswoman Lynn Valentine told the AP, though she had no immediate information about the deceased. At least four firefighters were hospitalized with second-degree burns.

California Gov. Jerry Brown has declared a state of emergency in Lake and Napa Counties as the region copes with its latest deadly blaze.

The Valley fire is one of 12 currently burning in California. Though it’s not the largest or the deadliest, it has engulfed more homes than any other blaze this year. As of late Sunday night, fire officials said that 400 homes, two apartment complexes, 10 businesses and more than 1,000 structures, such as barns and sheds, had fallen to the flames. According to Reuters, the Valley fire is the most destructive of the dozens of fires that have scorched the Western U.S. this year.

Overnight, the two towns at the center of the fire, Cobb and Middletown, became blackened shells of themselves. Both small, scenic communities of about 1,500 people each, they were rendered unrecognizable by Sunday morning.

“I’m standing in the middle of a bombed-out town,” Scott McLean, a battalion chief for the California Department of Forestry and Fire Protection, told the New York Times. “I’m on a block of burned-down structures. There’s the frame of a mobile home — that’s all that’s left. The cars are burned-out hulks. The trees look like skeletons. There’s a porch swing, a bathtub. I’m seeing the remnants of somebody’s life.”

The stories told by those who stayed put as the fire raged around them sounded like something from a war zone. David Hamilton, who was pedaling out of Middletown by bike Sunday morning, said he spent most of the night listening to the sound of propane tanks exploding as they were consumed by the flames.

“It was like bombs going off,” he told the L.A. Times. “Three going off at one time, kaboom.”

Francisco Cervantes sent his family away from their Middletown home, though he was sure that the fire would never reach their part of the valley. By the time he realized his mistake, it was too late — the blaze had boxed him in. There was no way to evacuate the area.

Instead, he spent Saturday night and Sunday morning fending off flames, he told the L.A. Times. When a nearby tree began to burn, he rushed over to tamp out falling embers. When the power flickered out and his hose went dry, he hauled water from his neighbor’s pool.

By daybreak, he sat exhausted on the wall outside his stucco home, surveying the devastation. A neighbor’s house had been reduced to rubble. A dead horse lay on the side of the road. But, like his home, a nearby goat shed was still standing, and inside it, a nanny and a billy goat were alive and on alert.

“Next time, I never stay home,” he told the Times.

The swiftly spreading Valley fire has destroyed hundreds of homes and forces thousands of residents to flee. (Reuters)

Those who did make it out had a different kind of war story. At the Napa County Fairgrounds about 30 miles south, evacuees sought food, a place to pitch a tent and any kind of solace they could find.

“My house burned down. Everything burned down,” 33-year-old Justin Olson told the Napa Valley Register. All his worldly possessions had been reduced to what he was wearing when he hopped into the pickup truck of a fellow evacuee Saturday: black pants, Jeff Burton NASCAR T-shirt, a crumpled, close-to-empty pack of Seneca cigarettes in his pocket.

“All you could see was this big wall of fire coming toward us,” Olson recalled.

Now he waits at the fairgrounds, homeless, car-less, but unscathed. Wondering what comes next.