On a cloudless autumn afternoon, sunlight sparkled on the water that had quietly swallowed a busy intersection to the north of San Francisco, as the surrounding rush-hour traffic slowed to a painful crawl.<\/p>\n
There were no crashing waves or storm surges to blame for the flood. Marin county was one of many areas up and down the California<\/a> coast affected by high tides last week, as parts of the Pacific swelled with excess warmth.<\/p>\n The submerged streets stood as an early signal of California\u2019s vulnerabilities as it braces for what could be a tumultuous winter.<\/p>\n \u201cIf you think this is bad, just wait until December,\u201d a state worker grumbled as he directed swarms of cars past the choke point toward a sidestreet.<\/p>\n Experts have warned that a potentially historic El Ni\u00f1o is brewing, with the power to unleash extreme weather around the world. The climate phenomenon, characterized by warmer than average equatorial sea surface temperatures, is already under way, according to federal forecasters, and it is expected to strengthen through the northern hemisphere\u2019s autumn and winter<\/a>.<\/p>\n California is poised to be in its crosshairs. Landslides, flash floods and encroaching sea levels are all on the menu \u2013 and they could all happen at once.<\/p>\n A flooded highway intersection in Mill Valley, California, as high tides inundated parts of the coast. Photograph: Gabrielle Canon\/The Guardian<\/p>\n \u201cWhat we\u2019re really looking at is the compounding element,\u201d Nick Brubaker, the chief resilience officer for the office of emergency management in Marin county said. The biggest concern isn\u2019t just rising tides. It\u2019s the way everything could collide.<\/p>\n Dangerous spikes in temperature are likely. Some areas could see supercharged storms and relentless rains. Others face explosive surf, strong currents and devastated marine ecosystems. The effects of El Ni\u00f1o will add an additional foot of sea level rise in California on top of the 8in to 12in caused by the climate crisis there over the last century, according to Michael Anderson, a state climatologist.<\/p>\n And in recent wildfire burn scars, including the slopes of Big Sur that burned this summer and neighborhoods devastated by the 2025 firestorm in Los Angeles, there will be higher chances of debris flows.<\/p>\n The risks are but a taste of what\u2019s to come as the world warms. Preparations are already under way at all levels of government as officials work to secure vital infrastructure, preset response resources and inform the public of the incoming hazards.<\/p>\n \u201cWe are trying to make sure that people are aware that this may be one of the most significant El Ni\u00f1o years that we\u2019ve seen,\u201d Brubaker said.<\/p>\n Preparing for a hot fall and a wet winter<\/p>\n California stretches across roughly 770 miles (1,240km), and its regions are likely to experience El Ni\u00f1o very differently. Southern California typically sees wetter winters in El Ni\u00f1o years, but that\u2019s not necessarily the case further north.<\/p>\n While the stage may be set for violent weather, it\u2019s impossible to forecast what will unfold. \u201cWhat the science supports is elevated risk,\u201d said Dr Ariel Cohen, a meteorologist for the National Weather Service, during a recent briefing held in Los Angeles. \u201cA strong El Ni\u00f1o shifts the probabilities \u2013 it does not determine exact outcomes.\u201d<\/p>\n With the potential for dangerous conditions already rising, emergency managers are planning for the worst.<\/p>\n Gavin Newsom, California\u2019s governor, issued a state of emergency<\/a> on 21 September to mobilize efforts and resources, kicking off a flurry of activity. Adverse conditions fueled by El Ni\u00f1o are already taking shape. A mass of warm water known as a \u201cKelvin\u201d wave<\/a> is crawling up the California coastline with the ability to raise sea levels by up to a foot.<\/p>\n A lifeguard keeps watch along a closed boardwalk as a wave crashes over a seawall on 7 September 2026 in Long Beach, California. Photograph: Mario Tama\/Getty Images<\/p>\n Along with coastal flooding from elevated sea levels and high tides, powerful storms swirling through the Pacific have made for an unusually busy tropical cyclone season. Hawaii is still recovering from a series of deluges<\/a> and strong winds that flooded roads and buildings, unleashed landslides and toppled trees. Swathes of the southern California coastline were hammered<\/a> by massive waves that damaged homes and devoured beaches.<\/p>\n Areas already hit hard are working to recover \u2013 and build resilience. In Long Beach, just south of Los Angeles, the seawall has been lined with large sandbags to reinforce spots where strong surf has burst through. In Orange county, roughly 690,000 cubic yards of sand is being pushed along the coastline. Workers are going door-to-door in San Diego\u2019s flood zones to help small businesses ready their buildings.<\/p>\n The Los Angeles county public works department has been assessing risks over the last six months, according to Mark Pestrella, its director, who said flood control systems are ready and optimized during a recent briefing.<\/p>\n Channels and debris have been cleared from drainages, 14 dams were tested and reservoirs prepared. These systems, he clarified, are designed to withstand a so-called \u201c100-year event\u201d, which he said had a roughly 1% chance of occurring in any given year. But El Ni\u00f1o could bump those chances higher.<\/p>\n \u201cWe are assuming it is going to rain and with El Ni\u00f1o we assume it is going to rain with high intensity,\u201d Pestrella said.<\/p>\n Of particular concern, he added, were the areas still in recovery from the devastating wildfires that swept across LA county in January 2025, consuming more than 16,000 structures. In Pacific Palisades and Altadena, the communities that were most intensely affected, homes and buildings are still being rebuilt. Pestrella said it takes five years for watersheds and hillsides to heal enough to withstand strong rains.<\/p>\n Along LA county\u2019s 23 miles of coastline, large berms and sand dune systems are being built on beaches to fight against erosion, according to Gary Jones, the director of Beaches and Harbors. That effort happens every year, but officials are starting a month and a half earlier than usual.<\/p>\n \u201cThis El Ni\u00f1o won\u2019t be the last one and unfortunately erosion at our beaches is becoming more and more common,\u201d Jones said.<\/p>\n Meanwhile, LA\u2019s office of emergency management director, Kevin McGowan, is juggling dangers on the other end of the hydrological spectrum: high heat and fire risks that are likely to linger into November.<\/p>\n \u201cWe are in the middle of fire season and about to head into a significant heatwave,\u201d McGowan said before a sweltering October weekend<\/a> that smashed several records<\/a> across southern California, noting that fire conditions can still peak through the winter months. \u201cPeople should continue to prepare not just for one hazard \u2013 but all hazards.\u201d<\/p>\n \u2018The sandbags are ready\u2019<\/p>\n For Mary Ellen Carroll, the executive director of the San Francisco department of emergency management, the good news is there is still time to prepare.<\/p>\n \u201cIt feels like I\u2019m planning for an earthquake, but I\u2019ve gotten two months\u2019 notice,\u201d she said.<\/p>\n Along with elevated flood risks around the port and the Embarcadero on the Bay side, and dangerous ocean conditions along the beaches, there could be long power outages during storms. For people that are more vulnerable \u2013 older people and folks that are medically dependent \u2013 \u201cit can get very dangerous quickly\u201d, she said.<\/p>\n While El Ni\u00f1o doesn\u2019t as directly produce more moisture-laden storms in this part of the state, elevated sea levels will continue to be a concern. Record high-tides<\/a> are likely between December and February next year. California king tides \u2013 when surf is highest \u2013 will occur during the week of Thanksgiving, the week of Christmas, and on the Martin Luther King Jr long weekend, making for a potentially dangerous holiday season.<\/p>\n A wave washes up near workers using heavy machinery to protect damaged beachfront homes on 14 September 2026 in Dana Point, California. Photograph: Mario Tama\/Getty Images<\/p>\n Back in Marin, where low-lying areas flood even without the added influence from El Ni\u00f1o, Brubaker said the county was rushing to clear drains and culverts, and installing temporary flood barriers.<\/p>\n They have also expanded their supplies of free pre-filled sandbags and generated detailed online interactives<\/a> so residents and visitors can more easily visualize their risks.<\/p>\n About 70 miles south, in the beachside tourist town of Santa Cruz, the emergency services manager, Meredith Albert, said this year\u2019s preparations fall in line with the challenges coastal communities have long faced. \u201cWe are building on what we all know have been our risks and hazards all along \u2013 for better or worse, they aren\u2019t a surprise,\u201d she said of the atmospheric river events, coastal erosion and flooding that can wreak havoc in any year.<\/p>\n Santa Cruz has seen its fair share of extreme weather. In 2024, a parade of storms<\/a> and violent surf knocked out the city\u2019s beloved pier, which only recently reopened<\/a>.<\/p>\n While there\u2019s careful consideration of overstating messages and emergency alert fatigue, Albert added that \u201cthe public messaging is ready to go. The sandbags are ready.\u201d<\/p>\n But the biggest priority is to ensure preparedness starts at individual and neighborhood levels \u201cand grows outward from there\u201d, Albert said. In Santa Cruz, they have planned neighborhood workshops where city staff will meet with small groups to discuss the dangers, what the city will be able to do and how people can help one another.<\/p>\n The goal is not to make Santa Cruz invulnerable. But building resilience in communities will be the key to navigating the uncertainties of when and how calamity could strike.<\/p>\n \u201cThose community connections are the difference between a disaster being something you can\u2019t come back from and something you can learn from.\u201d<\/p>\n It\u2019s a sentiment being echoed across the state.<\/p>\n \u201cWe are never going to have enough resources at the onset of a disaster to support every single person,\u201d McGowan cautioned in Los Angeles. \u201cOur communities are the fabric that gets us through these disasters \u2013 neighbors helping neighbors saves lives.\u201d<\/p>\n","protected":false},"excerpt":{"rendered":"On a cloudless autumn afternoon, sunlight sparkled on the water that had quietly swallowed a busy intersection to…\n","protected":false},"author":2,"featured_media":919864,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[22],"tags":[64,63,75,128],"class_list":["post-919863","post","type-post","status-publish","format-standard","has-post-thumbnail","category-environment","tag-au","tag-australia","tag-environment","tag-science"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts\/919863","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/comments?post=919863"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts\/919863\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/media\/919864"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/media?parent=919863"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/categories?post=919863"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/tags?post=919863"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}