LOS ANGELES (CBSLA.com/AP) — Stranded motorists were pulled from cars stuck on flooded Northern California roads as thunderstorms arrived Sunday as part of a massive winter storm that could be the biggest to slam the region in more than a decade.
Crews cleared trees and debris following mudslides caused by steady rain accompanying the system that could dump 15 inches in foothill areas as it gained strength throughout the day. Several feet of snow was expected at higher elevations in the Sierra Nevada.
Authorities reported rescues in Marin and Sonoma counties, including an operation along U.S. 101 where several people were plucked from submerged vehicles. No injuries were reported.
Officials urged residents to avoid driving through standing water and to stay off rural roads, where rescues could be difficult.
The storm was expected to bring heavy rainfall to the Southland Monday. Rainfall could start as early as midnight. The rain could be moderate to heavy, according to the National Weather Service, lasting through the morning commute and dropping a half-inch to one inch of precipitation in the L.A. Basin and 1 ½ inches in the mountain areas.
According to CBS2/KCAL9 Meteorologist Craig Herrera, the storm front would likely hit Ventura County by 3 a.m. before moving south into the L.A. Basin and the San Fernando Valley between 4 a.m. and 6 a.m. It would hit Orange, San Bernardino and Riverside counties between 6 a.m. and 9 a.m.
Meanwhile, all roads leading to Yosemite National Park’s valley floor remained closed amid fears that the Merced River could overflow its banks and cause major flooding.
“It’s kind of surreal how empty the park is. There’s nobody here,” said Gary Kazanjian, a freelance photographer who spent the night in Yosemite and drove out Sunday as part of a caravan of stragglers.
Authorities were watching rising water levels of several Northern California rivers, including the Cosumnes, Truckee, American and Russian.
Forecasters also warned of strong winds. A woman was killed Saturday by a falling tree on a San Francisco Bay Area golf course. Firefighters on Sunday rescued a man pinned under a toppled tree in Golden Gate Park. The homeless man had minor injuries and was taken to a hospital to be checked.
The storm surge stretching all the way from Hawaii — called an atmospheric river — comes as California enters its sixth year of drought. Each drop of rain is welcomed, but officials said several more big storms are needed to replenish depleted groundwater supplies.
The strong wet season began in October with more rain falling than in three decades, mostly in Northern California. Los Angeles, which will likely get the brunt of the latest system early Monday, is experiencing its wettest winter in six years, forecasters said.
The storm’s relatively mild temperatures will drive up the snowline to above 9,000 feet throughout the Sierra Nevada, causing runoff in the lower elevations, said Zach Tolby, a meteorologist with the National Weather Service in Reno, Nevada.
Flooding could rival the winter of 2005-06 that sent 5 feet of water into an industrial area in Sparks, Nevada. Crews worked to secure storage drums filled with hazardous materials to stop them from floating away as they have in past floods.
Another storm is forecast for Tuesday and with the ground already saturated, rain won’t seep into the soil quickly enough and extra runoff could end up in already swollen rivers and creeks, officials said.
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