Northern California Keeps Wary Eye on Flooding as Another Storm Approaches

Updated 4:45 p.m. Tuesday

Skip to:

Where can I find the latest on Bay Area weather?
How do I sign up for emergency weather updates?
How can I prepare for floods in California?

Northern California residents are bracing for another round of powerful storms this week after flooding from a New Year's Eve deluge killed one person, prompted the evacuation of more than 1,000 incarcerated people in a county jail and washed away a section of a levee system that protects mostly rural farmland.

Another strong storm with high rainfall rates and winds is headed for Northern California, expected to hit late Wednesday and last into early Thursday. On top of the New Year's Eve rainstorms, which saturated the soil, more water is likely to produce mild to moderate flooding, and some flooding on smaller river systems like the Russian River.

While smaller reservoirs are filling up, there is still plenty of capacity in larger reservoirs at the moment, given California's prolonged drought. The wet weather is expected to continue off and on for the next several days.

"The main concern really are the smaller watersheds and steep slopes, mudslides, shallow landslides, urban and creek flooding that could get quite significant for a period of time on Wednesday night in some locations, given that everything is now completely saturated and streams and creeks are already running high," said UCLA climate scientist Daniel Swain. "In some cases, there's some residual flooding already ongoing."

Swain said heavy precipitation and strong winds could also affect parts of Southern California as far south as Los Angeles County. There will be some flooding no matter what, he said, but the question is whether it's widespread minor-to-moderate flooding or significantly more severe.

"This is really going to help a lot with the short-term drought in Northern California, perhaps even raise short-term drought conditions," said Swain. "But it's going to take a lot more to completely obviate the longer-term multiyear drought impacts. And in the broader Colorado River Basin context, this event isn't going to do very much at all."

In south Sacramento County, crews rushed to repair a 200-foot section of a roughly 34-mile levee system along the Cosumnes River that protects just over 53 square miles of mostly vineyards and cattle ranches. Crews hope to finish repairs before the next storm is forecast to hit on Wednesday. If they can’t, they’ll seal whatever progress they have made with plastic and sandbags and hope for the best.

A powerful “atmospheric river” storm dumped up to 5 inches of rain in the Sacramento region on Saturday, said Eric Kurth, a meteorologist with the National Weather Service.

Rainfall in downtown San Francisco hit 5.46 inches on New Year’s Eve, making it the second-wettest day on record, behind a November 1994 deluge, the National Weather Service said.

Another powerful system is expected Wednesday and Thursday and could bring up to 3.5 inches of rain in the Sacramento Valley and up to 3 feet of snow in the Sierra. Then, yet another storm is forecast to arrive this weekend.

In the Bay Area, a National Weather Service forecast warned Wednesday’s storm could cause widespread flooding and power outages, calling it “truly a brutal system that we are looking at [that] needs to be taken seriously.”

Repeated storms make floods more likely. “It’s something we’re going to be keeping a close eye on, especially with elevated stream levels [and] saturated ground from our previous storm,” Kurth said. “With what we’re going to be getting ... adding on to that previous storm is really the big issue.”

The Wilton Rancheria Tribe said floodwaters threatened to disturb ancestral burial sites along the Cosumnes River and asked the public to report to them any sightings of washed-up artifacts or remains, but to leave them undisturbed. Unlike most major California rivers, the Cosumnes River is not dammed, meaning there is no basin to collect excess water during major rain events.

“We’re just kind of at nature’s mercy,” said Mark Hite, a member of the board for Reclamation District 800, which oversees the levee system.

Residents on Monday were still drying out from Saturday’s storm, which prompted officials to order the evacuation of the Point Pleasant community near the Cosumnes River in South Sacramento County. That included 1,075 incarcerated people plus staff at the Rio Cosumnes Correctional Center, who evacuated as a precaution though the jail had not flooded. Incarcerated people were taken to nearby jails with no timetable for their return, according to Sacramento County Sheriff’s Office spokesperson Amar Gandhi.

Emergency crews rescued motorists on New Year’s Eve into Sunday morning. On Sunday they found one person dead inside a submerged vehicle near Highway 99, which Dan Quiggle, deputy fire chief for operations for Cosumnes Community Services District Fire Department, told The Sacramento Bee. Highway 99 was closed for much of the day Sunday, but has since reopened in both directions

State highway workers spent the holiday weekend clearing traffic-stopping heavy snow from major highways through the Sierra Nevada.

Near Lake Tahoe, dozens of drivers were rescued on New Year’s Eve along Interstate 80 after cars spun out in the snow during the blizzard, the California Department of Transportation said.

The rain was welcomed in drought-parched California. The past three years have been the state’s driest on record, but much more precipitation is needed to make a significant difference.

Resources for tracking Bay Area weather

Plenty of online resources and apps are available for tracking weather in real time, especially ahead of rain, storms and extreme conditions. Below is a list of sites KQED regularly uses in our reporting.

Websites to track basic weather information

Comprehensive scientific sites for weather watch

Northern California Keeps Wary Eye on Flooding as Another Storm Approaches

Resources for tracking Bay Area weather

Where to sign up for Bay Area emergency weather alerts

Signed up.