Gov. Gavin Newsom proclaimed a state of emergency Monday as California prepares for an El Niño event that could become one of the strongest on record, according to the governor’s office.
El Niño can shift weather patterns around the world and contribute to extreme weather, including drought, flooding and heat, according to the University of California Agriculture and Natural Resources.
The Copernicus Climate Change Service reported that August 2026 was the joint-warmest month ever recorded globally, tied with July 2023. In September, extreme heat contributed to several power outages across neighborhoods near USC’s University Park Campus, according to the Los Angeles Department of Water and Power.
“It was definitely hot, really, really hot for the first couple of weeks, and I feel like our power grid was also not really able to keep up with that,” said Akansha Sallakonda, a senior majoring in quantitative biology. “I do think that as climate change gets worse, we will be unprepared to deal with more extreme weather.”
Here’s how climate experts say the historic El Niño event could affect USC and Southern California as it progresses.
What is El Niño?
El Niño is an increase in sea surface temperatures in the eastern and central Pacific Ocean, according to the U.S. Geological Survey. The agency says the climate pattern develops when low-level surface winds that normally travel from east to west along the equator weaken or begin blowing in the opposite direction.
El Niño developed earlier this year and has continued to strengthen. The governor’s office said there is a greater than 90% chance of a very strong El Niño this fall and winter. The World Meteorological Organization said there is a nearly 100% likelihood that El Niño will persist through February 2027.
According to the governor’s office, El Niño can bring more frequent, intense storms to California, increasing the risk of flooding, landslides, debris flows and erosion.
“It’s knocking at our door right now, and it’s only ramping up,” said Ian Walker, a professor of geography at the University of California, Santa Barbara. “It’s safe to say that the risks, which are the things that are exposed to the storms and erosion, will increase, and that the hazards, that being the floodwaters and the erosion events, will also increase through the rest of this El Niño.”
How can students prepare for El Niño conditions?
Karla Heidelberg, a professor of biological sciences and environmental studies and director of USC Sea Grant, said students should prepare for weather they might not be used to, including intense storms and strong winds.
“We’re going to have a rough winter,” Heidelberg said. “If this comes to full fruition, we’ll have to be very diligent about making sure that people are safe and protecting property as much as we can, but it’s going to be a real challenge this year.”
Students can use the Los Angeles County Public Works’ flood map to check flood risk in their area and sign up for local emergency alerts.
The governor’s office also recommends having an evacuation plan and keeping an emergency kit ready in case of flooding or other severe weather.
Areas recently burned by wildfires face an increased risk of flooding, debris flows and mudslides during heavy rain, according to the governor’s office. That could create additional risks in areas affected by recent fires, including the Palisades and Eaton fires.
How is El Niño impacting Southern California’s environment?
El Niño and unusually warm ocean temperatures can significantly alter marine ecosystems, shifting where species live, feed and migrate.
During strong El Niño events, tropical and warm-water species can move farther north along the California coast. The Scripps Institution of Oceanography says species such as hammerhead sharks have previously appeared farther north as warm-water habitat expands.
Heidelberg said a sicklefin devil ray was recently spotted by a USC diver near Catalina Island. She also said sea turtles have been migrating north from tropical waters.
Scientists at Scripps say warm-water events can affect migration patterns, food availability and the geographic ranges of marine species. During previous strong El Niño events, Southern California has seen greater numbers of warm-water species, including tropical sharks.
Although the exact local effects of El Niño remain difficult to predict, officials say Californians should prepare for the possibility of heavy rain, flooding, strong winds and coastal impacts this fall and winter.
Heidelberg said individual lifestyle choices that reduce greenhouse gas emissions can also contribute to broader efforts to address climate change, which can intensify some extreme weather risks.
Edited by Natalie Cerna and Zayane El Solh