Two quick observations about droughts in Southern California: They are common and can be two-faced.
First, Southern Californians know droughts.
We went through a prolonged drought from 2012 to 2016, and before that there were the droughts of 2007-09, 1987-92 and 1976-77. And later we saw two rainy seasons from October to May of 2022-2023 and again in 2023-2024 which left SoCal saturated with above-average amounts of rainfall.
This local climate pattern is frequently referred to as a wet-dry cycle by meteorologists.
“It has been really dry since April/May of 2024. Since that time, there hasn’t been a lot of rain in Southern California. This could be the beginning of another drought,” cautiously summarized Brandon Goshi, water resource group manager for Metropolitan Water District of Southern California.
The (non) rainy season
From June 1, 2024 through Tuesday, Jan. 21, only 3% of the historical average amount of rainfall for this time period has fallen in Los Angeles County — about 0.16 of an inch reported AccuWeather. And just 0.03 inches fell at LAX since Oct. 1, not enough to leave spots on the windshields of cars in the long-term parking lot.
If Goshi is counting on this dry bubble bursting by early spring, he may be wishing on a rain cloud.
That’s because the Climate Prediction Center, a division of the National Oceanic and Atmospheric Administration (NOAA), forecasts “drought conditions will persist through the end of April” in Southern California, said Brad Pugh, a meteorologist at the Climate Prediction Center based in College Park, Maryland, on Thursday, Jan. 23.
The mountains and foothills of Los Angeles County are in “extreme drought” conditions, about 36% of the county, explained Pugh. That’s one category shy of hitting the highest level, “exceptional drought,” and three higher than the lowest, “abnormally dry.” The rest of the county is in severe drought.
More than three-fourths of Riverside County is under “extreme drought,” as is 100% of Imperial and San Diego counties. All of Orange County and most of San Bernardino County are listed as “severe drought,” one level less than extreme, according to the U.S. Drought Monitor, maintained by another NOAA institution, the National Drought Mitigation Center in Lincoln, Nebraska.
The switch to drought conditions in Los Angeles County — where the devastating Eaton fire in Altadena and Pasadena, and the Palisades fire along the coast — occurred only in the last few weeks, after climate scientists measured rainfall at below the 10% average, and tested soil moisture and stream flows, Pugh said.
If dry winds meet drought plus ignition sources, as we saw with the Eaton and Palisades wildfires and more recently, the Hughes fire in the Castaic area, could mean months of fire alerts with millions of Southern Californians sitting anxiously with go-bags at the very least.
Cracks in the drought wall
But this drought wall — technically not a full drought until 12 dry months have passed — will show some cracks this weekend as rain and mountain snowfall is forecasted from Saturday through Monday.
In short, the drought reveals its other face.
Meteorologist Carol Smith with the National Weather Service said the chance of measurable rain is between 60% and 90%. “Measurable rain is not a trace,” she explained on Jan. 22.
It will hit Southern California and bring one-tenth to one-half an inch of rain over most of the region. Eastern L.A. County, near the Eaton fire, will get more, between one-half an inch to 1.5 inches of rain, Smith said.
The rain will fall at a steady pace. It is not expected to move debris, ash and soot into waterways or turn fire-burned hillsides into mud, the NWS reported.
However, if the 10% to 20% chance of thunderstorms pans out, that could change.
The cold storm is predicted to drop as much as 4 to 8 inches of snow in the San Gabriel Mountains at elevations between 3,500 feet and 4,500 feet, Smith said.
Right after the storm leaves, the area returns to dry conditions, she said.
Paul Pastelok, a long-range forecaster with AccuWeather, said there are minimal chances of rain in the region after this storm exits.
“The best chance of rain over the next six weeks appears to be Feb. 10-23,” he said in a prepared statement.
Are droughts ‘normal’?
Precipitation won’t be enough to erase the drought or remove dry conditions, said Pugh.
That’s because of La Niña, which brings a cooling of the sea surface temperatures in the equatorial Pacific Ocean, he said. “During those times, it tends to be drier than normal.”
La Niña pushes the storm tracks to the northern Pacific. When the storms go north, they often miss Southern California, Pugh said. This is the opposite of El Niño, often associated with wetter years.
Metropolitan Water District’s Goshi said the agency, which provides water to 19 million Southern Californians, has been adapting to swings from dry to wet years and to climate change making these swings more intense.
During the last two years of heavy rainfall, it has amassed 3.8 million acre feet of water in storage. One-acre foot equals 325,851 gallons and is enough to supply about three families in Southern California a year, according to the MWD.
MWD’s storage in reservoirs and in underground aquifers is about a two- to three-year supply, even without another drop of water, he said. “We are able to use those investments to make it through multiple dry years,” he said.
Snowpack in the Sierras is at 123% of normal. Sierra snowmelt is a major source of water to Southern California. It’s other outside source, the Colorado River watershed, is at 115% of normal, Goshi reported. So this “drought” is not affecting Southern California’s water supply.
Bob DiPrimio, president of San Gabriel Valley Water Co., which services 290,000 people in 16 cities, said they draw from wells from two vast underground aquifers in L.A. County, called the Main San Gabriel Basin and the Central Basin.
“Now we are in decent shape,” he said. But if the drought goes into a second year, less rainfall means less water flowing into the underground basins. He may have to buy imported water from MWD that comes from Northern California and/or the Colorado River basin, which is standard procedure for augmenting well water supplies.
“We have redundant, reliable water systems in place,” he said on Jan. 24.
Drought, dry brush and fires
“It is normal in Southern California to have extended periods of drought and extended periods of rainfall,” said Rick Halsey, a fire ecologist with the California Chaparral Institute in Escondido on Jan. 23.
Ecosystems are used to this seesaw effect, he said and fire is part of the Mediterranean climate of Southern California. Destruction of habitat, such as the loss of natural flora including chaparral, is a greater factor in wildfires than global warming, he said.
The dwindling chaparral — indigenous plants that are more fire resistant than invasive plants that grow quickly and take their place — has contributed to most wildfires, Halsey said.
But the biggest factor, aside from winds and low humidity, are people, he said. When humans step in, or as Halsey calls this, “stupid people doing stupid things,” disaster often strikes.
Unlike other parts of the world, Southern California rarely gets lightning-caused fires or fires combusting through natural means. Fires here are usually manmade, either by accident or intentionally, he said.
Power lines serving houses in the urban interface can blow down in the wind and spark, and set the grasslands ablaze. This relates to what he calls unproductive brush clearance.
Too often, crews beneath power lines, and people clearing around the base of their home, scrape away the natural chaparral in the name of creating “defensive space” and that leaves room for grasses to spring up, making the fire danger worse. He cited a recent fire in Colorado that burned grasses exclusively and then destroyed many homes.
“Defensible space is pretty irrelevant when a fire’s embers jump for miles,” Halsey said. “Maybe we should try something different, since that it not working.”
He has installed roof and eaves-mounted exterior sprinklers at his home. He recommends all communities invest in these and other home hardening methods. People who have swimming pools should have a pump that supplies water to sprinklers that can douse houses with water.
“When that house is saturated it is not going to ignite,” he said.
He said urban ecosystems near homes in Southern California are not adapting too well to climate change and loss of habitat. But he encourages ordinary citizens to work on plantings, restoration and talking to leaders about climate change as well as his ideas about fire prevention.
A UCLA study found that white-faced male capuchin monkeys in Costa Rica who experienced intense physiological responses to drought conditions could adapt and survive extreme droughts. Studies of how animals adapt to changes in temperature and rainfall can help scientists understand how humans and other species can better adapt to the effects of climate change, the UCLA researchers concluded.