LOS ANGELES — Waves of heavy rain pounded California on Thursday, filling normally dry creeks and rivers with muddy torrents, flooding roadways and forcing residents to flee their homes in communities recovering from wildfires.
The storm turned on Southern California after walloping northern parts of the state and southern Oregon on Wednesday. A home slid down a hill in Sausalito, north of San Francisco, and a woman was rescued from the wreckage. At least 50 homes were evacuated after the mudslide struck a neighborhood, KNTV reported.
Flash flood warnings blanketed a huge swath east and south of Los Angeles, including areas burned bare by a summer wildfire in the Santa Ana Mountains, where people were told to evacuate.
Conditions proved too wet for the Genesis Open at Riviera Country Club in Los Angeles, where play was halted after less than an hour. The Knott’s Berry Farm and Six Flags Magic Mountain theme parks closed.
The National Weather Service reported staggering rainfall amounts, including more than 9.4 inches (24 centimeters) over 48 hours at one location in the San Bernardino Mountains.
But trouble persisted in the saturated north, with flood warnings in effect for a large area of the upper Central Valley and around the San Francisco Bay Area.
The storm followed more than a week of severe weather in the Pacific Northwest and was the latest in a series of storms that has all but eliminated drought-level dryness in California this winter. It’s fueled by an atmospheric river — a plume of moisture stretching across the Pacific Ocean nearly to Hawaii.
Nearly 37 percent of California had no level of drought or abnormal dryness, the U.S. Drought Monitor reported Thursday. About 10.5 percent of the state was in moderate drought, just over 1.6 percent was in severe drought. The remainder was in the abnormally dry category. The numbers reflect data gathered up to Tuesday.
Atmospheric rivers are long bands of water vapor that form over an ocean and flow through the sky. Formed by winds associated with storms, they occur globally but are especially significant on the West Coast. When an atmospheric river originates near Hawaii it is commonly referred to as a “Pineapple Express.”
Even before the height of the storm, mandatory evacuations were ordered near the wildfire area in the Santa Ana Mountains where officials said there was a high risk of debris flows.
Tim Suber said he has lost count of how many times his hillside neighborhood in Lake Elsinore has been evacuated between last summer’s devastating wildfire and this winter’s succession of storms.
“I’m not going this time,” Suber said Wednesday after authorities warned him that he could end up trapped if roads flood. “I’ve got 35 chickens and a daughter who won’t leave them behind. So we’re staying.”
The storm also led to severe turbulence on a flight Wednesday from Southern California to Seattle. Five passengers suffered minor injuries, and the Delta Air Lines flight was forced to make an emergency landing in Reno.
Photos on social media showed a drink cart upended and snacks and soda cans littering the aisle. One passenger tweeted that the plane did two nosedives in “crazy turbulence” but the crew “handled it perfectly.”
In Northern California, winter storm and backcountry avalanche warnings were in effect in the snow-laden Sierra Nevada.
A state of emergency has been declared in Shasta County because of significant storm damage, and thousands of utility customers lost power in the region. A fire in the county seat of Redding last summer destroyed more than 1,000 homes and killed eight people.