The Burning Wind

Every autumn the Santa Anas come howling in from the desert. Impossible to predict, they have eluded definition by the scientists who study them. No wonder the winds put us on edge

Only two spectacles guarantee L.A. national attention every year, the Academy Awards and autumn’s Santa Ana wind fires. Both are huge productions accompanied by costs in the millions; both deliver movie stars in varying states of distress and questionable attire.

A town known for extremes deserves a contrary wind, and L.A.’s Santa Anas bestow a season of disaster while also polishing the most harmonic of days. They are the Eastside’s revenge on the Westside, returning the smog bank over the San Gabriel Valley to origins near the coast. Cities windier than Los Angeles exist in the United States—Cheyenne, Wichita, Amarillo, Des Moines—but the Santa Anas get all the attention. As name recognition among weather systems goes, they have the highest Q rating west of the Rockies. They are meteorology’s own Madonna.

One of the strangest experiences L.A. offers newcomers is waking to a Santa Ana. The previous fall night may have been cool, even misty. After sunrise, the initial view outside is of a blue void that glimmers with surreal clarity. A dry static charge has replaced the evening fog. One glides through the humidity-free air rather than walks in it, an encounter with absence that’s like a subtle flavor inexplicably missing from a favorite dish. The morning news features live feeds of small mountain towns staggered by high winds and wildfire. Yet stepping into the garden, one feels no breeze at all. Somewhere the Southland is being blown to hell, and L.A. has never looked more promising.

Atop the Santa Monica Mountains and in Orange County, Santa Ana winds have been clocked at speeds above 110 mph—the force of a Category 3 hurricane like Katrina when it made landfall in Louisiana. Pairing disaster with grandeur, the winds have acquired mythological powers. Alternately they are said to incite distraction, sadness, numb brutality, Chunky Monkey binges. Swiftly violent, lacking motive, the Santa Anas are the only winds that have been channeled into a literary genre, L.A. noir. They connect the famous opening lines of Raymond Chandler’s story “Red Wind”—“Santa Anas that come down through the mountain passes and curl your hair and make your nerves jump”—to works by Joan Didion, linking L.A.’s arcadian dazzle with its nightmares.

Usually wind blows into L.A. from the Pacific, a daytime airflow generated as the sun warms the desert and coastal plains. When in early October the year’s premier Santa Ana stirs, it wakes at night. The sun is no longer dominant, the desert is cooling, and the Santa Ana can begin its flight to the sea. Other things awaken with it. Dogs pace their yards, livestock low in their pens, and firebugs stepping outdoors feel the heat and itch of the wind between their fingers. At what hour do our first Santa Ana fires ignite? Midnight, or two in the morning, or at four a.m. They tend to start in Malibu, where the winds initially alight. Only later do the mountains of Orange County and San Diego glow, as gusts pitch from north to south and fire agencies scramble to keep abreast.

If you wanted to pick a spot at which the Santa Anas gather their force—a point of embarkation for the 50, 60, 90 mph blasts that career through Soledad Canyon and into Santa Clarita, San Fernando, Simi Valley, and Malibu—you could do no worse than to settle on the trim front yard of Gary and Celeste Thornhill. The Thornhills live on the scrubby edge of southern Palmdale. They manage a public storage facility—it is their backyard—off Avenue R, a mile from the San Andreas Fault.

Gary Thornhill has led a life intimate with disaster. He is 70 years old and was raised in the town of Santa Ana, where, he says, “the wind blew so hard that the windows whistled, and when Modjeska Canyon burned you could hear the pop and crackle.” For two decades he hustled as a newspaper photographer, capturing floods, fires, temblors, and highway wrecks. As a kid Gary imagined that the Santa Anas were born in nearby Santa Ana Canyon. Today he knows better. He is a National Weather Service volunteer, measuring the speed and humidity of winds that course across his front yard before they enter Soledad, where Celeste grew up. “In the big blows back then with the static charge,” she says, “you could watch the sparks fly off your ears.”

Each day Gary records the temperature, barometric pressure, humidity, and wind speed—four parts to an equation that helps identify a Santa Ana. His marriage to Celeste is a working union. Celeste types out the numbers, and Gary faxes them to the National Weather Service, which in turn issues warnings to fire agencies when the Santa Anas are imminent.

The Santa Anas create L.A.’s best beach days and the planet’s worst fire weather. If you look at just three years—2007, 2003, and 1993—more than 6,000 homes were destroyed by Santa Ana fires, housing loss that surpasses that of the Northridge earthquake. Given the annihilating potential of the Santa Ana winds, you’d think by now we’d be able to define them. Hurricanes are broken into five categories, tornadoes into six. Every day the Thornhills send the National Weather Service four numbers supposedly used to decode the presence of a Santa Ana. The problem is, nobody can agree on what constitutes a Santa Ana. There is no definition for North America’s most famous wind.

Well, not one, anyway. The Jet Propulsion Laboratory has defined the Santa Anas as “dry north-easterly winds having speeds in excess of 25 knots.” The Lawrence Livermore National Laboratory has said that preconditions for a Santa Ana include humidity levels below 40 percent and high atmospheric pressure in the desert. Other studies have pointed to the relative humidity at LAX and the wind speed at Ontario airport. A definition that came out of UCLA in the ’60s was as snappy as the federal tax code: The Santa Anas, it said, are northerly winds in the San Fernando Valley moving faster than 10 mph with humidity levels under 30 percent, coupled with a temperature decrease of at least 15 degrees between Santa Monica and Palmdale. This year a new UCLA study reduced them to mountain pass winds averaging speeds of five meters per second or higher. Eric Boldt, a warning coordination meteorologist at the Oxnard National Weather Service office, where the Thornhills’ numbers arrive, has more or less thrown his hands up in the air. “I think we used to have a definition,” he says. “Now we just call any offshore wind a Santa Ana.”

The approach of a hurricane can be monitored for weeks, but our capacity to forecast Santa Ana winds remains limited. We are unable to predict the appearance of a Santa Ana by more than a few days in advance. We cannot know what this year’s Santa Ana season will look like. We don’t understand why some years they blow softly or why in others they torment us. We can’t explain why one fall is plagued by Santa Ana events, each lasting nearly a week, while the next year sees only daylong events. Fire agencies speak of engaging wildfire in militaristic terms, yet they own practically no good intelligence on their superior enemy, the wind.

“It is really strange,” said Alex Hall, who teaches in UCLA’s department of atmospheric and ocean sciences. “We have more variability in our climate than likely any other place on Earth. Along with precipitation, Santa Anas are the main thing that shapes our climate. Yet an amazingly small amount of scientific writing has been produced on them. Today, with the Internet, you can quickly size up the tree of knowledge for Santa Ana winds—and it’s a twig.”

Hall was tanned and trim from swimming, with the stubble of beard that signifies summer break in college departments. With a former graduate student named Mimi Hughes, he has spent three years developing the latest computer modeling of Santa Ana wind currents. He also had the best off-the-cuff definition of a Santa Ana that I’d heard. “Basically they’re the opposite of precipitation,” said Hall, sitting in his office at UCLA. “They’re extreme drying events where, instead of seeing a flow from the ocean to desert—which is precipitation—we experience an opposite flow that drops down and desiccates the landscape.” Hall grew up in Chicago and left in 1989 to study physics at Pomona College. “That was my first experience of Santa Anas,” he said. “The air was crystal clear, and it was very hot. For me, they became the epitome of beautiful California climate because that was the day they always took the campus picture.”

As Hall earned his Ph.D. at Princeton, he found the view of California from New Jersey obscured by clouds. “The big East Coast schools of meteorology,” said Hall, “have always been preoccupied by the classic storms you see in the mid-latitudes over North America and Europe. When you arrive here, you are overwhelmed by the diversity of our weather. Every few miles you drive, you run into yet another climate. But the things that make up L.A.’s climates, such as Santa Anas, get comparatively little attention.”

Winds similar to the Santa Anas have been studied around the world: the zonda of Argentina, the samiel of Turkey, the koembang of Java. They all belong to a group known as foehn winds—downslope air currents that warm as they descend, losing humidity in the process. At least, that is the definition you would find in Foehn Winds for Dummies. Foehn winds remain a curiosity of meteorology, their classification based on an anthology of competing theories instead of one concise proof. As with Canada’s chinook, a foehn that melts winter snowpack, they are known for their heat.

Hurricanes are created by low-pressure systems (which are lighter than the surrounding atmosphere) that suck in air and then braid it into swirling, humid storms. The Santa Anas are the product of high-pressure systems that push air out pell-mell in the form of dry winds. Such systems are tremendous in stature. They resemble a Bundt cake as large as 4,000 feet in height and 1,000 miles in diameter. During fall and winter, the jet stream—a river of cold air meandering high above the northern hemisphere—dips in latitude over the continental United States. On it rides a series of high-pressure systems that skid in from the Pacific. Sometimes they detach from the jet stream and become lodged for days between the Colorado Rockies and the Sierra Nevada—an expanse of the West known as the Great Basin. Spinning clockwise, they spray their winds out onto the Great Basin states—Utah, Idaho, Nevada, California. When those winds reach the desert wall of the San Gabriel and San Bernardino mountains, they slip through the lowest gaps like water: the Newhall Pass at 750 feet; the San Gorgonio Pass at 2,600 feet; the Cajon Pass at 4,200 feet. The mountain passes squeeze the winds and increase their speeds, just as water shoots from a nozzled hose. Once they descend the steeper lee slopes of the mountain front, they become what we know as the Santa Ana winds.

That, essentially, is the origin and path that Alex Hall and Mimi Hughes believed in before they created their computer model and looked at a couple of compelling questions. The first had to do with high-pressure systems and why one the size of the United Kingdom can sit on the Great Basin while L.A. experiences no Santa Anas.

“What’s interesting,” said Hughes, “is that L.A. has lots of days with really strong high winds originating in the Great Basin. But they’re not dropping down to the ground, so we don’t call them Santa Anas. They just blow right over without us ever knowing they’re here.”

Hughes’s computer model has helped document why Great Basin winds stay aloft some days. “We looked into those days,” Hughes said, “and we found a temperature gradient between the desert and L.A.” If it’s warmer in Palmdale than in Los Angeles, according to Hughes’s model, Great Basin winds may never fall. L.A. dodges a Santa Ana.

But this leads to a more puzzling question: Why is it that L.A. gets Santa Ana winds when the Great Basin’s pressure supply is on empty? “What this means,” said Hughes, referring to the movement on her screen, “is that if it’s cold enough in the Mojave Desert, we don’t need Great Basin winds to create a Santa Ana.” Instead, it turns out, the Santa Anas are somehow generating locally without even a breeze from Utah. Other experts suspected as much, but Hughes’s model verges on being proof—and means predicting Santa Anas just got a lot tougher.

Eric Boldt had said he was impressed after viewing Hughes’s work. Still, I wanted to know if it was odd to study a wind with no definition.

“It was definitely a minus,” Hughes said. “In my analysis I had to state that this is what prompted the Santa Anas, and people are always going to argue with me on what a Santa Ana is. It can all seem so abstract.”

“But there is such a thing as a Santa Ana?” I asked.

“Well, yeah, right…?” Hughes trailed off, turning her answer into a question and looking unconvinced. “How would you—” she broke off again and smiled. “I mean—you mean—is there such a thing as a Santa Ana?”

A moment passed.

“The point is,” Hughes said finally, “I’m not going to wake up screaming some night, having realized this computer model is wrong.”

The first time Bill Clayton heard the phrase “Santa Ana wind” he was driving with his dad in San Diego County near the mountain town of Julian. It was 1956, and Clayton’s father was the fire chief at Camp Pendleton. West of Julian, by a spot named Pine Hills, a blaze had started the day before. Something awful had happened overnight, and the man and boy—Bill Clayton had just turned 16—were traveling to assist.

There were 11 sleeping bags laid out in a field when the two arrived and groups of men standing around talking. Hours earlier in a canyon the fire had changed direction, surprising a crew of forest service employees working with prison inmates to rout the flames. Now those men were in the bags.

“My dad didn’t want me to see the bodies,” says Clayton today, “so he kept me at a distance. But I saw them anyway. Before that, I didn’t know much except that the wind blew. I didn’t know what a Santa Ana was. It was kind of sobering.”

Fourteen years later a Santa Ana wind had San Diego under a fire siege. Clayton had become a strike team leader, in command of five engine crews that September day. Since morning he’d been chasing a fire with a head start of 90,000 acres. The engines streamed through Lion Valley, dodging pickups and felled power lines and a horse trailer that was in flames. There was no organization in place, no division command, no resources on the way. Clayton called dispatch for orders. “Go to Harbison Canyon,” dispatch said.

It was 1970, California’s worst wildfire season before this past summer. In 13 days, 773 fires ignited, leaving behind enough charred landscape to form a mile-wide highway from San Diego to the Oregon border. Fed by the Santa Ana winds, fires burned across Malibu, Simi Valley, Camarillo, Woodland Hills, Brea, Hacienda Heights, Palos Verdes, Griffith Park, Chatsworth, Pomona, and Laguna Beach. As is true today, San Diego County saw the most severe Santa Ana fires because its cities and towns are dispersed across chaparral rangeland.

Three hundred houses sat in Harbison Canyon. A window detonating from a home showered one of Clayton’s engines with molten glass. The truck burst into flames, and he ordered it abandoned. Superheated, Harbison ignited around the strike teams—50 acres in two seconds. A cinder tornado descended as propane tanks exploded into demented flights over the glowing scenery. Wind blew so hard it drove the crews’ water jets back onto their faces.

Just then a sheriff pulled up beside Clayton and asked, “Who’s in charge here?”

“I am,” Clayton replied.

“Well, you got a problem,” the sheriff said.

Clayton noticed that the plastic light atop his cab had melted onto the engine’s roof. “I already thought I had a problem,” he said to himself.

In fire agencies they say if you want to pinpoint where the Santa Ana winds will blow this fall, find the nearest, oldest fire chief before he retires. After commanding the attack on 2003’s devastating Cedar Fire, Bill Clayton retired. Before that day he was the nearest, oldest chief—San Diego County’s walking wind database. “We get the state’s worst wind-driven fires,” says Clayton. “But all our weather technology is still reactionary. When conditions are just right I can tell you which canyon a fire will go down. But we don’t figure out ahead of time what the Santa Ana winds will do. We don’t know when or why they will surface.”

Leaving Harbison, Clayton trailed the sheriff’s car and came across two engines that had crashed head-on in the smoke. Men were scattered everywhere. An engine was aflame, and someone’s spleen had ruptured. Right there they fought more fire, losing 103 houses in 15 minutes to the wind. They found a five-year-old boy standing in the road and chased after a mother who had driven off without her son. After 48 hours they went to sleep on someone’s lawn. When Clayton awoke, he was temporarily blind from blisters on his eyes.

As hard as San Diego County suffers today, development and weather patterns over the next two decades guarantee increasingly destructive fires—what will surely be the nation’s worst conflagrations. Until recently, among the few undisputed facts about the Santa Anas was that they have their own season, October to March. That was before people started taking California’s changing climate into account.

Bill Patzert works in the earth science building at JPL in Pasadena. Several years ago the Bush administration cautioned the agency against drawing parallels between global warming and human activity. Patzert was one of a few scientists who ignored the order. “Anybody who says we need another study to prove global warming exists has their head up their tuchas,” he told me.

It was June, and Patzert had strange news. “Remember how hot it was last week?” he asked. For ten days temperatures in Los Angeles had stayed above 100 degrees. “Well, that was a weeklong Santa Ana,” he said, leaning back and smiling. “In June.” Patzert and others think the Santa Ana season is expanding all the way into summer. “That,” says Eric Boldt, “is something we are definitely seeing. We are having more and more offshore events in summer where we did not before.”

Patzert believes that the typical annual range of Santa Ana days in the past has run from 15 to 70. “But what is the trigger?” he asked rhetorically before mentioning the May 2007 Griffith Park fire. “That was a Santa Ana out of season. Then came the October fires. The Santa Anas just kept coming. Why? Well, in years of drought, as we are experiencing now, more high-pressure systems stall in the Great Basin, making us vulnerable to longer Santa Ana events. And California is only getting warmer and drier.” In 2007, said Patzert, L.A. experienced 72 days of Santa Anas. Should the number of days keep increasing, Southern California might see fire seasons that run not from October through November but from May through December.

Fire agencies, however, don’t focus on winds. They focus on fuels. Clearing a chaparral stand is easier to undertake than doing something about the breeze. Max Moritz, who runs the Moritz Lab at UC Berkeley, told me, “This is the source of my frustration and the story of my latest crusade. I’ve been yelling for years that winds like the Santa Anas are one of the key missing pieces in understanding fire.”

Moritz was vacationing in Lake Tahoe when we spoke. It was a beautiful June day. The lake sparkled beneath pleasure boats, but Moritz was in a mood. “Right now we have a thousand fires burning in California,” he said, “and we can’t say what the fire weather will be in two weeks. The California Department of Forestry throws billions of dollars at wildfire, they’re losing every year, and not a scrap of funding goes to the question of wind.” Moritz reeled off a short list of what we could know: not just where and when the Santa Anas will hit but also how bad they will be for fire crews. “Beyond that,” he said, “it’s amazing we don’t even have fire severity maps that include weather patterns like the Santa Anas. The last comprehensive study was done in the ’60s.”

In 1964, a UCLA atmospheric scientist named James Edinger attempted to map the Santa Ana wind currents. From data hand collected off a network of wind stations, he and a group of meteorologists created a sheaf of maps. They remain the most detailed documents we have of where and when the Santa Anas will appear, and about a dozen people are aware of them.

Without computer models, Edinger’s team discovered striking phenomena. For example, the Santa Anas are assumed to move from areas of high pressure to the low pressure found over the Pacific. Edinger found a wind jet ten miles wide that blows out of the Cajon Pass and streams through Santa Ana Canyon before curving inexplicably northward. It then shoots into the Newhall Pass, opposite the path that any fire chief will tell you a Santa Ana takes. He discovered a vortex near downtown that forms in the morning, spinning and scattering winds in all directions. And he lamented that the most serious lack of wind knowledge (still true today) concerned the communities on the San Gabriels’ southern front.

“I honestly think that we could build high-resolution computer maps of these wind channels,” Moritz answered when I asked why no one had improved on Edinger’s work. Moritz described an animated map that would follow winds above L.A. during wildfires. “It would take some fat computers to get decent digital resolution of the landscape, but you could do it.”

Air does not move over L.A. as it does over other North American cities. Instead of steadily slipping by us, our onshore flow is blocked by mountain ranges and trapped under an inversion layer. That boxed atmosphere builds a reactor about three kilometers high that holds 6 billion tons of air. Within the reactor every carbon particle imaginable is warming in the sun, creating a chemical stew that heats the city below.

In his office at Caltech in Pasadena, Richard Flagan and I were looking at some photos of particles he’d caught in a trap set on his roof. Flagan is an aerosol scientist. He is interested in tiny airborne particles. The particles in Flagan’s photos were extremely tiny—iota 20 microns across—such as pollen spores one hundredth the size of a pinhead. Outside his second-story window a row of floss silk trees swayed sensually in the breeze. Lacking seasonal pollen, they couldn’t catch
Flagan’s eye, not like the spore-heavy ginkgoes and hornbeams that waved his way.

“Now,” said Flagan, reaching behind him, “take a look at this picture.” He laid a second photo on the table between us. Far fewer particles floated in its frame. Their size, however, was notable. Just one of them could have eaten all the others in the first frame.

“When the Santa Anas blow,” Flagan said, “and the hot wind comes down off the desert, it is quite strong. It picks up a lot of things, some of them very large.” Riding in on the wind is the powdered detritus of human existence: ground-up tires, decayed landfill, the rubble of old silver mines. We breathe it all in. “This,” said Flagan, tapping the second photo, “is what arrives in a Santa Ana.”

What arrives on that air affects people differently. In Austria and Switzerland, where foehn winds similar to the Santa Anas have been studied for decades, all kinds of physical and mental ailments have been linked to them: migraine headaches, depression, neuralgia, poor concentration, menstrual difficulties, insomnia, and circulation problems. Office sick days spike during foehn events, traffic accidents increase, and suicide rates rise. Foehn winds are believed to create electromagnetic pulses and generate concentrations of positive ions, which may increase levels of serotonin, a chemical messenger in the brain that can alter mood. The Swiss even have a term for those more affected than others by the winds. They are said to be foehnfühlig.

Southern California has no equivalent studies, but crime statistics gathered during last October’s worst Santa Ana are intriguing. Winds blew heavy Sunday, October 21, through Thursday, October 25. A review of the LAPD’s crimes database for that period shows that officers turned in 294 reports of domestic abuse. Over five consecutive days the previous week—October 14 to 18—just 241 similar reports were turned in, meaning there was a 22 percent rise of reported domestic abuse during the high winds. The Santa Ana Police Department, reviewing the same dates, found a 30 percent rise in reported domestic abuse.

“Meek little wives feel the edge of the carving knife and study their husbands’ necks.” So goes another line from the opening of Chandler’s “Red Wind.” Chandler describes a wind in which “anything can happen,” incoherence reigns, and “every booze party ends in a fight.” For such a short description it casts a long shadow. “I don’t know if I shied away from describing the Santa Anas because of Chandler,” says the novelist Michael Connelly. “But I was always aware that anything I wrote about them would be compared to the master.”

The wind, variously, has been said to be named after Santa Ana Canyon, the Mexican general Santa Anna, Saint Anne’s Day, and the etymologically incorrect “Santana” for Satan. Spooked by the name, the Santa Ana chamber of commerce persuaded the Los Angeles Times in 1902 to keep it out of the paper’s stories. Through the 1940s, the Times referred to the Santa Anas as our “northern winds.”

We look now for smoke on the breeze come October, but the Santa Anas of the early 20th century were real Dust Bowl gales, occult and cruel, propelling Mojave sand and pulverized granite into the air. Stories of rural mishap and farmland despair were common. Nine hundred acres of topsoil vanished one afternoon into the blue. In Glendale 2,000 trees were ripped from the ground by a single blast. Cornfields were leveled, orchards toppled. When the winds steamrolled over the Cajon Pass and into Riverside County, they stripped citrus trees of every leaf. Houses and barns were uncoupled from their foundations. In Pasadena in the ’20s, a small home was picked up by a Santa Ana, carried over a neighboring house, and then thrown into a two-story home, leveling it. Years later, a Pomona chicken farmer named Clarence Easley was repairing a roof when the wind carried him aloft, ferrying Easley 110 feet before dropping him. He is the only man reported to have been blown to death by a Santa Ana.

Our endless growth of subdivisions has slowly done away with those storms, restraining the winds’ progress in stucco mazes and concealing topsoil that once easily took flight. “The Santa Anas are a reminder of all that we have denied,” says Janet Fitch, whose novel White Oleander begins in a blustery Santa Ana. “It’s a wind of the desert,” she says. “A wind of everything that is uncontrollable and harsh. It blows away the illusions of this place—patience and goodwill and optimism that come with forgetting—and robs us of the illusion of our dreamlike existence.”

Whenever the Santa Anas are mentioned we seem to revert to a steppe culture of superstitious nomads, imbuing every light and rock we see with a name and ego. “No matter how destructive an earthquake is,” says Connelly, “I never think of them as malevolent. But Santa Anas are acts of nature that have always had an aura of malevolence to me.” From Beowulf to Lear on the heath, winds have forever been antagonistic elements in literature. But no one calls a hurricane “malevolent.”

“We are amused by your interest,” Santa Ana’s fire chief, Marc Martin, replied when I asked if he took guff for having the infamous wind’s name on his engine fleet. Martin was gracious, inviting me into a large conference room. Outside, the sky over Santa Ana was crystalline and seemingly endless. A visitor to the town can be taken aback by the size of that sky and the sight lines that avenues of mostly single-story housing afford. When a century ago that panorama was obliterated by a desert blast, it must have been an awesome spectacle.

“We don’t discuss the winds often,” Martin told me. “But you find pretty quickly there are two schools of thought, one based on the Santa Ana Canyon, one on the devil—even if ‘Santana’ doesn’t mean ‘devil.’ We do see people acting erratically during Santa Ana winds, people getting angry, people having emotional breakdowns. The concept of a devil wind that causes mankind to do bad things it wouldn’t normally do makes sense.” Martin’s speech had turned solemn. “Bad things happen during Santa Anas,” he said. “I believe that. They are devil winds.”