Rachel's Remnants Wreck Long Beach Homes and Boardwalk as Forecasters Warn of Historic El Niño Winter

A weakened Tropical Storm Rachel did real damage to Southern California over the weekend of Oct. 10-11. Forecasters say it is a preview of the winter ahead.

Rachel had weakened to a post-tropical cyclone by the time it approached California. It still sent waves into Long Beach homes, destroyed a boardwalk and forced residents to flee, with some houses at risk of collapse.

Long Beach and Newport Beach

At least nine Long Beach homes have been declared unsafe to enter, the Long Beach Post reported. Displaced residents can't go back in to retrieve their belongings. The same outlet reported the storm has cost the city more than $1 million from its emergency reserves.

Newport Beach declared a local emergency and briefly closed its piers, citing "higher-than-normal surf" that inundated streets. By Monday, Oct. 12, cleanup was under way and the piers had reopened. Officials still advised residents to stay cautious near the water.

Farther south, the remnants also hit Mexico's Baja California.

Las Vegas Tied a Record

The storm's reach went well inland. The National Weather Service said Las Vegas tied its all-time daily rainfall record for October, with 1.08 inches into Sunday morning. Water rushed over a street near the Strip.

An Unusually Violent Pacific

Rachel arrived in the middle of an unusually violent Pacific hurricane season. The last five Pacific hurricanes all reached major status, with winds of at least 111 mph, and one set a record for time spent at Category 5.

"This year, just everything that forms is just lasting a long time and getting really powerful," Phil Klotzbach, a Colorado State University storm researcher, told the Associated Press. He called the past month "berserk."

The Kelvin Wave Factor

Scientists say the coastal flooding was driven in part by a Kelvin wave, a slow-moving pulse of water beneath the ocean surface that is one of El Niño's first effects.

According to NASA, it works like an "underwater freeway" moving heat from west to east across the Pacific. Such waves can raise sea levels along the California coast by several inches to more than a foot. On their own they can cause minor flooding.

The damage comes when that pulse stacks with high tides, storm-driven waves, El Niño's thermal expansion of seawater and long-term sea level rise from human-caused climate change. Josh Willis, a project scientist for sea level missions at NASA's Jet Propulsion Laboratory, called Kelvin waves "the heartbeat of El Niño."

"El Niño is a good opportunity to see where our vulnerabilities are throughout the state," said Mark Merrifield, director of the Scripps Center for Climate Change Impacts and Adaptation. Parts of the Bay Area have also seen coastal flooding.

What Forecasters Expect This Winter

The worse threat is still ahead. Daniel Swain, a climate scientist with the University of California Agriculture and Natural Resources, said a stronger El Niño produces stronger atmospheric rivers. These are long corridors of water vapor that dump heavy rain or snow on land.

"There aren't necessarily more of them, but atmospheric rivers are more intense during a strong El Niño like this one," Swain told USA Today. He added that strong El Niños also increase the frequency of other storms in California.

On his Weather West blog, Swain wrote that this will be the strongest and easternmost-centered El Niño on record, "if it isn't already." He said the tilt toward wet and stormy conditions in California will be "profoundly unsubtle."

The risks are highest in Southern California. El Niño winters there carry elevated threats of landslides, debris flows and flash floods. Those dangers grow around burn scars, including neighborhoods still recovering from the 2025 Los Angeles firestorm.

Breitbart reported that Gov. Gavin Newsom has declared a state of emergency so that extreme-weather precautions are in place for the months ahead.

The Longer Coastal Outlook

California's Fifth Climate Change Assessment, a state-commissioned report, sketches the longer-term picture for the same coastline. It projects that Southern California could lose 30 to 70% of its beaches over the next several decades. Almost half of beach cliffs are likely to retreat by 30 to 80 feet by 2100.

A 1.6-foot rise in sea level by 2060 would leave low-lying areas particularly vulnerable, including the ports and Santa Monica, Venice and Redondo beaches. One estimate in the report puts 15,000 people in Los Angeles County at risk of exposure to flooding.

"There are things in there that are hard to digest," said Abby Edwards, senior deputy director for the Governor's Office of Land Use and Climate Innovation, which led the assessment.

Those are projections, not forecasts for this winter. They do show what the coastline faces as storms and sea level rise combine.

It remains unclear how much of the damage this winter can be prevented. Long Beach is already out more than $1 million, with at least nine homes deemed unsafe to enter, before the rainy season begins.