Updated Feb 5, 2024 - Science

In photos: Atmospheric river triggers evacuations and outages in California

An aerial image taken on Sunday, Feb. 4, of flooding in Petaluma in the San Francisco Bay Area of California, which was slammed by the first atmospheric river last week. Winds gusted to 70-90 mph in many peaks across the entire Bay Area and Central Coast Sunday and there was "a marginal threat" for severe weather across the region overnight, per the NWS. Photo: Josh Edelson/AFP via Getty Images

Editor's note: See Axios' latest coverage on the California storm.

A powerful storm slamming California triggered evacuations and left over 800,000 residents without power into Monday, as forecasters warned "dangerous flooding rains," strong winds and heavy snow would impact central and southern areas for several days.

The big picture: California Gov. Gavin Newsom issued an emergency proclamation for eight southern counties, including Los Angeles — which was at "high risk" from potentially deadly flooding during this atmospheric river event that Los Angeles Mayor Karen Bass said had "the potential to be historic."

A car drives through a flooded road in Topanga, California, on February 4, 2024. The US West Coast was getting drenched on February 1 as the first of two powerful storms moved in, part of a "Pineapple Express" weather pattern that was washing out roads and sparking flood warnings. The National Weather Service said "the largest storm of the season" would likely begin on February 4.
A car drives through a flooded road in Topanga, California, on Feb. 4, as the storm prompted road closures and disrupted flights across the state. Photo: Apu Gomes/AFP via Getty Images
 Residents stand along a flooded street as a powerful long-duration atmospheric river storm, the second in less than a week, impacts California on February 4, 2024 in Santa Barbara, California. The storm is delivering potential for widespread flooding, landslides and power outages while dropping heavy rain and snow across the region.
Santa Barbara residents stand along a flooded street on Feb. 4, when Santa Barbara County was among the areas affected by evacuation orders. Photo: Mario Tama/Getty Images
A giant tree fell on a house on El Grande Dr. in San Jose, as atmospheric river storms hit California, United States on February 4, 2024.
A giant tree fell on a house in San Jose, California, during the atmospheric river storm event on Feb. 4. Climate change is making extreme precipitation events more common and intense across the U.S. and the world. Photo: Tayfun Coskun/Anadolu via Getty Images
A person stands near a boat which washed ashore (L) as a powerful long-duration atmospheric river storm, the second in less than a week, impacts California on February 4, 2024 in Santa Barbara, California. The storm is delivering potential for widespread flooding, landslides and power outages while dropping heavy rain and snow across the region.
A person near a boat washed ashore (left) in Santa Barbara during the storm on Feb. 4. "Strong winds will cause high surf up and down the California coast, whipping rain at lower elevations and blowing snow across the Sierra are also likely," the National Weather Service noted early on Feb. 5. Photo: Mario Tama/Getty Images
A vehicle got off the road on Highway 101 in Sunnyvale as atmospheric river storms hit California, United States on February 4, 2024.
A vehicle after being swept off the road on Highway 101 in Sunnyvale as the atmospheric river hit on Feb. 4. The city in Santa Clara County was among the worst affected by power outages, according to utility tracker poweroutage.us. Photo: Tayfun Coskun/Anadolu via Getty Images
 Heaven clouds and rain are seeing from Topanga, California on February 4, 2024. The US West Coast was getting drenched on February 1 as the first of two powerful storms moved in, part of a "Pineapple Express" weather pattern that was washing out roads and sparking flood warnings. The National Weather Service said "the largest storm of the season" would likely begin on February 4.
Storm clouds and rain over Topanga in Los Angeles County on Feb. 4. A flash flood warning remained in effect for the county through midnight. Photo: Apu Gomes/AFP via Getty Images
A flooded street in Santa Barbara, California on Feb. 4.
A flooded street in Santa Barbara, California, on Feb. 4. Some universities in California have said they're moving to remote classes on Feb. 5 due to powerful winds and rain. Photo: Mario Tama/Getty Images

Editor's note: This article has been updated with more photos and further details on the storm.

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