Live updates: Atmospheric river triggers intense flooding around Bay Area
SAN FRANCISCO - This story is developing, check back for regular updates
An atmospheric river continued to drench the Bay Area on Friday, triggering flash flood warnings due to the intense rainfall.
San Francisco Peninsula
In the afternoon, motorists were urged to stay off the roads in San Francisco and San Mateo County as the first batch of flash flood warnings from the National Weather Service went into effect.
The flash flood warning issued for San Francisco expired at 3:45 p.m., while the one for San Mateo County lasts until 5 p.m. The NWS replaced San Francisco's flash flood warning with a flood warning until 6:45 p.m. as the heaviest rain ended in the late afternoon.
The weather agency said San Francisco has already received between 0.5 and 1 inch of rain, with an additional 1 to 3 inches possible.
"Do not attempt to travel unless you are fleeing an area subject to flooding or under an evacuation order," warned Mayor London Breed.
The NWS emphasized that the heavy downpours that trigger flash flooding can be "life-threatening."
East Bay
The East Bay received between 0.7 and 1.2 inches of rainfall on Friday, with meteorologists anticipating an additional 1 to 3 inches.
Alameda and Contra Costa counties were under a flash flood warning set to expire at 6 p.m. The National Weather Service said that Oakland, Berkeley, Richmond, and El Sobrante could experience flash flooding.
Hayward, San Leandro and Castro Valley are also affected by a flash flood warning until 7:45 p.m.
North Bay
The North Bay bore the brunt of the season's strongest atmospheric river — a long plume of moisture that forms over an ocean and flows through the sky over land.
On Friday, the system unleashed relentless rain, leading to mudslides.
The California Highway Patrol reported at 2:10 p.m. that mudslides closed Silverado Trail in Napa County. The road was shut down from Oak Knoll Avenue to Yountville Cross Road.
A flood warning was also in effect for the Russian River near Guerneville, where waters are expected to peak at 33 feet.
"We will see the Russian River come up. It's just gonna come up to minor flood stage, right around 33 feet tonight and stay at that point until about 5 p.m. Saturday afternoon," said Sonoma Emergency Management Director Jeff Duvall.
In Santa Rosa, a cascade of water and mud carried cars, trees and debris downhill. Noah Menton shared video of his car ensnared by a mudslide on Mark West Springs Road.
South Bay
The storm brought wet conditions to the South Bay and the Santa Cruz Mountains, with rainfall blanketing roads during the evening commute.
The California Highway Patrol reported rockslides on Highway 9 and Highway 35, but they did not lead to any road closures.
In San Jose, crews were on alert on Friday for locations prone to flooding.
Residents were encouraged to take proactive measures before the teeth of the storm struck, to reduce the risk of localized flooding.
"I think we're 'rain ready' here. We prepare all year long, clearing out the 30,000 storm drains here in the city," said Mayor Matt Mahan. "Our partners at Valley Water are constantly working to clear the channel and make sure that our waterways are clear."