Emergency management officials Tuesday told L.A. County supervisors they’re preparing for the worst ahead of this winter’s potentially historic El Niño weather system.
The climate pattern usually brings significant rain and ocean swells to Southern California, elevating the risk of flooding and mudslides.
Forecasters say El Niño has already formed in the tropical Pacific Ocean and that there is already a 90% chance of a strong El Niño in our region this year.
What you need to know about El Niño
El Niño years can be associated with lots of rain in Southern California, though there’s no guarantee of a deluge.
And wet winters aren’t always disastrous. What matters is how much water falls within how much time. In fact, going back to when modern records began in 1950, most of the years when we’ve seen the highest flood-related costs were not during El Niño events.
But there are concerns beyond rain for late 2026 and early 2027.
El Niño this time will coincide with another natural phenomenon — the highest tides of the year in a nearly two-decade cycle known as “the declination of the moon.” We’re reaching the max this winter, according to Scripps scientist Mark Merrifield.
Because El Niño warms the ocean, it also raises sea levels temporarily. On top of that there’s an unprecedented level of human-caused global warming in the mix — that has already raised sea levels by as much as a foot along California’s coast over the last century, and is making normal weather patterns more extreme.
“So we start adding these things up, and they’re actually not so small anymore,” said climate scientist Daniel Swain. “The risk of coastal flooding is actually very high and almost guaranteed.”
It’s not only the coast — inland areas, especially along creeks and rivers, are also at risk due to more extreme rainfall driven by El Niño as well as human-caused global heating, Swain and other experts said.
How the county is getting ready
The county’s Office of Emergency Management said it plans to hold a practice El Niño response exercise on Sept. 13. It will include county departments and community disaster management coordinators.
“ Most importantly, the exercise will allow us to identify gaps and response actions that we can continue to work on throughout the storm season,” said Kevin McGowan, director of L.A. County’s OEM.
Crews with L.A. County Public Works are working to inspect and clear all of the county’s flood control infrastructure, like storm drains and debris catch basins, in advance of any storms. Public Works Director Mark Pestrella said the infrastructure should be fully prepared by Oct. 15.
Pestrella also said his agency is watching the Eaton and Palisades fires’ burn scars, which are particularly susceptible to flooding and mudslides. He also urged homeowners to be aware of older burn scars.
“Look for hillside slopes that come down onto the property, and the vegetation is burned and still scarred, we want them to contact us directly,” Pestrella said.
What you can do
Emergency managers are urging at-risk residents — both homeowners and renters — to invest in flood insurance ahead of this winter, as it is not included in standard policies. They also said now is the time to fix leaky roofs and make sure drains are working properly.
During the presentation, officials also talked about their efforts to protect low-lying areas of the coast from flooding driven by both rain and high surf and warned that parts of Pacific Coast Highway are highly vulnerable to erosion.
Another area both emergency managers and county supervisors hope to prioritize is flood planning and emergency shelters for unhoused individuals in flood-prone areas.
At the end of the day, forecasters reminded the board that they can’t predict when rain will come or where it will fall. And emergency managers said they are preparing for the worst, regardless of what El Niño will actually bring this winter.