LOS ANGELES (AP) – A late fall storm drenched California with rain and dumped nearly three feet of snow to help bolster the vital Sierra Nevada snowpack but also triggered mud flows, flooded roads and traffic snarls as it tapered off early Friday.READ MORE: Tributes For Fallen Elk Grove Police Officer Ty Lenehan Pour In From Law Enforcement Across The Region
With thousands of acres of wildfire burn scars all over the state, authorities were warily monitoring barren slopes where parched earth soaked with rain can cause life-threatening mudslides.
Mud from the San Gabriel Mountains flowed into the foothill city of Duarte east of Los Angeles before dawn, affecting 18 homes where residents were told to not to leave, KCBS-TV reported. Firefighters rescued two people stuck in cars.
Two people stuck in a possible homeless encampment on a small island in the swollen San Gabriel River had to be hoisted to safety by a Los Angeles County sheriff’s helicopter.
In Sacramento, firefighters evacuated 10 adults and 13 dogs living in homeless encampments on islands in the American River as water levels rise.
Torrential rain fell in the coastal area between San Francisco and Los Angeles near the landmark Hearst Castle late Thursday. A nearby mountain spot where a huge wildfire burned in summer had received 3 inches of rain. The National Weather Service issued a flash-flood warning for the burn area, saying debris flows were a strong possibility.
In the Sierra Nevada, the Tioga Pass entry point to Yosemite National Park received 35 inches of snow in 24 hours, the weather service said.
Building snowpack in the Sierra is critical for California’s water supply after five years of drought.
Roads into Yosemite Valley were open again Friday after being closed overnight due to potential flooding. The Merced River crested below flood stage, resulting in no major damage to park roads or operations.
The storm entered the northern end of the state early Thursday and moved south, continuing to drop rain through the Friday morning rush hours across Southern California.
In Hollywood, hundreds of people were pelted by rain for hours Thursday night as they stood outside trying to get into a rare Metallica concert at a small venue, the Henry Fonda Theater.READ MORE: Bay Area Senator Proposes 12-Year-Olds Should Have Vaccination Rights Without Parents Consent
In Lancaster, north of Los Angeles, people out in the rain and wind were happy for the wintry holiday vibe.
“Just all of the sudden a little storm is kicking in,” Kara McDonald told KTTV-TV as she shopped in an elf hat. “We can sit around the fire and drink some hot chocolate.”
The storm caused worry in some spots like burn areas, where fire station were handing out sandbags.
“We’re concerned about mudslides and flooding,” Los Angeles fire spokeswoman Margaret Stewart said.
Get out quickly if “things go bad,” she urged residents of foothill and burned areas. “Don’t take the risk of being trapped in a mudslide.”
Earlier Thursday, the San Francisco Bay Area was hit with one of its heaviest storms in an already wet season, with a small town in the North Bay receiving nearly 7 inches of rain in 24 hours.
More than 100 flights in and out of San Francisco International Airport were cancelled and about 360 were delayed for minutes to hours because of weather concerns, said Brian Horne, airport duty manager.
Venado, a remote former lumber town west of Healdsburg, was hit the hardest as the storm moved from the North Bay into San Francisco and the Central Coast.
Some creeks in those counties were over flood stages.
San Francisco recorded more than an inch of rain in 24 hours, with areas further north seeing 2 to 4 inches and 5 to nearly 7 inches recorded in some areas of the Sierra Nevadas, along with at least one wind gust of over 100 mph.
In Healdsburg in Sonoma County, antique dealer Greg Sheldon said driving conditions were difficult.
“Some of our streets are flooded here. I had two feet of water in one of my lanes,” said Sheldon, who works at Antique Harvest. “There’s just tons of water coming off, the ground is so saturated right now. Every field is a big lake.”
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Copyright 2016 The Associated Press.