Why Doesn't It Snow in L.A. Anymore? | KCET
Why Doesn't It Snow in L.A. Anymore?
I have some bad news for Angelenos dreaming of a “White Christmas” this year: you were probably born a half-century too late.
Snow once fell on the Los Angeles coastal plain with some regularity – on average, about once per decade. Since official records were first kept in 1877, the downtown Los Angeles weather station observed measurable snowfall three times, in 1882, 1932, and 1949, and news reports recorded snowfall elsewhere in the Los Angeles Basin in 1913, 1921, 1922, 1926, 1944, 1957, 1962 – and then never again, for 54 years running.
Yes, Los Angeles is in the middle of a 54-year snow drought, and with each passing year snowfall becomes increasingly less likely – although it’s still technically possible in 2016. (And indeed, snowfall at higher elevations and in inland valleys is more common; a 1989 system dropped several inches on the San Fernando Valley but missed the coastal plain, and a 2007 storm dusted the canyons above Malibu with powder and dropped hail-like graupel on L.A.'s Westside.)
“Given the right meteorology we could still have a ‘White Christmas,’” Bill Patzert, a climatologist at NASA’s Jet Propulsion Laboratory, told me. “In 2050, no way!
More Weather History
Of course, snowfall has always been relatively unusual on the coastal lowlands of Southern California (or at least it has been since the dawn of the Holocene). “Because of our proximity to the Pacific,” Patzert said, “below-freezing temperatures are very rare. Our Mediterranean climate makes us mellow meteorologically. It smooths out the extremes in weather.” It would take the collision of moist marine air with an “extreme excursion of the Polar Jet Stream that brings below freezing temperatures” to blanket Los Angeles in white.
An L.A. blizzard, in other words, has always inhabited the margins of possibility, but a snow drought of this length seems to be unprecedented. For generations, Angelenos could count on waking up, at least once or twice in their lives, to a wintry scene: children pelting each other with snowballs beneath powder-dusted palm trees.
A Jan. 12, 1882, snowfall left the town’s “old timers … perfectly thunderstruck,” the Los Angeles Times reported, although the paper did acknowledge two previous snowfall events over the preceding twenty years. The Los Angeles Herald, meanwhile, couldn’t help chiding Southern California’s boosters for their over-the-top promotion of the region’s Mediterranean climate, asking, “how’s that for Semi-Tropicalia?” Atop a Spring Street jewelry store, someone gathered a 15-pound snowball (reports did not say how that ball was used), and a group of sport hunters suited up to track rabbits in the snow-covered countryside – only to watch the snow melt beneath their feet before reaching the rabbit grounds.
Fifty years later, on Jan. 15, 1932, what the Times described as “a genuine, old-fashioned Midwest snow flurry” made national headlines and brought a record 2.0 inches of snow to downtown Los Angeles. Albert Einstein, a visiting professor at Caltech, bemoaned the weather, noting to the Times that he and his wife “left Germany for sunshine.” On the frozen streets and sidewalks of downtown Los Angeles, six Angelenos slipped and were hospitalized, including a traffic officer who fell in front of a streetcar (his injuries were not fatal.)
This freak weather incited madness across the Southland. In the San Fernando Valley, coyotes emerged from the foothills in unusual numbers; terrified residents called the police, who shot several of the animals. In the San Gabriel Valley, a riot broke out in front of Pasadena Junior College when students streamed out of their classrooms to lob snowballs. As the icy missiles flew across Colorado Boulevard, windshields were cracked, street lamps smashed, and spectators bombarded. Four police officers soon arrived to disperse the crowd, but the students surrounded them, let the air out of their patrol cars’ tires, and pelted the officers with rock-filled snowballs. Only when a reinforcement army of some 30 policemen arrived, armed with nightsticks and tear-gas shotgun shells, did the riot subside. Seven rioters were jailed and two bystanders hospitalized. Faculty members professed bafflement, noting that the students were usually so well behaved.
Still, no storm incited as much wintry chaos as a January 1949 system that lingered for three days and dropped several inches of snow on the lowlands. Icy conditions forced the CHP to close the Pacific Coast Highway. White powder dusted the tops of palm trees from Santa Monica to Laguna Beach. In the San Gabriel Valley, orange growers burned smudge pots in a futile effort to protect their crops from frost, and in the Santa Monica Mountains the canyon roads became impassable; an accumulated foot of snow trapped nearly twenty automobiles in Laurel Canyon. The Southern California Gas Company reported record demand as nighttime lows dipped into the 20s and furnaces blazed around the clock.
It was a Jan. 21, 1962, storm that last deposited even a trace amount of snow on downtown Los Angeles. Only flurries fell on the Los Angeles Basin, but the snowfall was much heavier in the Santa Monica Mountains and San Fernando Valley. The 101 freeway became a slushy, treacherous skid zone through the Cahuenga Pass. Highway crews were caught off guard; Topanga Canyon Road closed until a snowplow could arrive, as did Sepulveda Boulevard. And no one was caught more unprepared then Richard Nixon, then campaigning for governor, who that day appeared in Sunland-Tujunga’s March of Dimes parade. Sitting in an open car in his light summery suit, Nixon waved to thinning crowds as sometimes-heavy snowfall chilled the parade route.
Why do such wintry scenes now seem to be a thing of the past?
I asked three scientists to speculate about the causes behind L.A.’s snow drought: JPL’s Patzert; Eric Boldt, a meteorologist with the National Weather Service’s Los Angeles/Oxnard forecast office; and Daniel Swain, a climate scientist at UCLA’s Institute of the Environment and Sustainability and author of the popular Weather West blog.
Good scientists that they are, they cautioned me that they could only draw tentative conclusions from the limited data. “Part of it could just be luck,” Boldt noted. Swain echoed him: “It's often hard to come to conclusions about trends in the occurrence of events that were very rare in the past, and potentially have become even more so.”
But all three pointed to a culprit you’ve no doubt already suspected: a warming climate.
Los Angeles today is roughly five degrees Fahrenheit warmer than it was a century ago, according to Patzert. We can attribute about half that increase to the urban heat island effect – artificial ground surfaces soaking up more thermal energy than natural ground cover. “The other half,” Patzert said, “is man-made global warming.”
Swain pointed to a “strong atmospheric warming trend California has experienced since the 1950s” and provided the two plots below, which show average daily and minimum overnight wintertime temperatures for the South Coast Basin from 1896 to 2016. “It's pretty easy to see that temperatures have drifted progressively farther away from the freezing point over that interval.”
And Boldt noted that minimum temperatures have been especially sensitive to the warming trend. “We routinely see [them] breaking records more so than high temperatures,” he wrote. Our nights, in other words, are getting even warmer than our days.
Five degrees of warming may have pushed a weather phenomenon from the margins of possibility into the realm of pure fantasy. We might never see another snowy day in Los Angeles.
That fact may not alarm many Angelenos, but a related phenomenon should. In the Sierra Nevada (Spanish for “snowy range”), progressively smaller snowpacks and earlier meltoffs – caused, like L.A.’s snow drought, by climate change – are making a mockery of the range’s name. Snowfall on the coastal plain has never been important resource, but snowfall on the Sierra Nevada supplies millions of Southern Californians with water by way of the California and Los Angeles aqueducts. We may not miss our snow, but we shall certainly miss our water.
This is a special time of year for the seagulls on Anacapa Island, the largest breeding ground for the Western gull in the Western U.S. The blooming wildflowers on the island make for a romantic setting for mating season.