Bay Area weather: Atmospheric river causes SFO flight delays, North Bay power outages

An atmospheric river arrived in the Bay Area on Wednesday, bringing heavy rain and wind to the region. The storm system first moved across the North Bay and is expected to spread further south later in the week, KTVU's meteorologists said.

Storm conditions knocked out power to nearly 10,000 PG&E customers in the Bay Area on Wednesday afternoon, with the North Bay and South Bay being impacted the most with 4,319 and 2,947 customers without power, respectively.

North Bay

The National Weather service issued a flood watch for parts of the North Bay and into Lake County, which will continue through Saturday. The agency warned of flooding along streams, creeks and roadways.

A wind advisory is also in effect in parts of the North Bay, San Francisco and the Pacific Coast through early Thursday. These regions may see wind gusts of up to 55-65 mph. 

According to KTVU meteorologist Roberta Gonzales, the North Bay will receive five to 12 inches of rain between Wednesday and Sunday. 

In Santa Rosa, the roads were a mess Wednesday as steady rainfall clogged drains. Industrial Avenue was among the first to flood, with water reaching half-foot deep in some spots as city crews worked to clear the drains.

The storm could bring historic rainfall levels.

"It's unprecedented. You know, like 9 inches in three days is something that nobody is really ready to handle," said Jack Gleason, of Santa Rosa.

Gleason, a carpenter with Mike Papola Custom Cabinetry, filled 37 sandbags on Wednesday to protect the Santa Rosa business.

At the Santa Rosa Municipal Services Center yard, the sandbag station was busy with residents in the pouring rain, shoveling dirt into the free sandbags to protect their businesses and homes.

"It's really wet. I walked out in the fields with my dogs this morning. My feet were sinking. Already," said Harry Strouse, a Santa Rosa resident who lives on Occidental Road across from a winery, "If it keeps going, people are going to be in trouble."

Santa Rosa Fire Department spokesperson Will Powers said the department's swift water rescue teams are on standby and watching the creek levels, and can be deployed within 15 to 20 minutes, if needed.

San Francisco

The rain moved in to San Francisco in the morning hours Wednesday.

South of the Golden Gate Bridge, residents can expect an estimated 1 to 6 inches of rain, with the heaviest rain expected Friday.

By 2 p.m. San Francisco International Airport reported 300 flights had been delayed and 50 had been canceled. 

Travelers curled up to wait it out Wednesday, and hoped for the best. 

"The scheduled departure was 1:15 p.m., start boarding at 1:15 p.m.," said Muhammad Ali. "Now, the flight is taking off at 3 o'clock. It hasn't had any updates as to whether it will be delayed beyond 3 o'clock. But, as of right now, I'm banking on it being 3 o'clock."

A steady stream of vehicles pulled into San Francisco's Department of Public Works lot, picking up sandbags. 

Dick Morten picked up bags this morning, saying with rain in the forecast he didn't want a repeat of past years' flooding. 

"We got bags last year, and it kept the rain coming from our neighbors's property down onto our house," said Morten. "But, the bags are getting old, so we're going to replace them."

The department is warning the city to brace for several days of wet weather. 

That means keeping an eye out for flooded intersections, slick roads and water-laden trees.

"When there are a lot of leaves on the trees, that means there's a lot of water that can get on the leaves and that makes the trees heavier, and if a big windstorm comes in that means they could fall a little bit easier," said Rachel Gordon from DPW. "So we really are paying attention to what's going on on the streets."

DPW is asking anyone who sees a tree or a branch that looks like it's in danger of falling to contact 311 to have the city come and trim or cut the limb or tree. 

RELATED: Latest Bay Area Weather Forecast

Much of the Bay Area's coastline is under a high surf advisory until 6 a.m. on Friday. The advisory applies to North Bay coastal areas near Point Reyes, through the San Francisco Bay and down to Monterey County and Big Sur.

The National Weather Service is warning of dangerous swimming and surf conditions.

East Bay

The atmospheric river didn't make a huge splash in the East Bay upon its arrival. Scattered showers fell over Oakland and Hayward during the afternoon, but rainfall is expected to increase this week.

South Bay

The South Bay saw partly cloudy skies with chances of rain in the forecast as the majority of the storm activity on Wednesday was focused in the North Bay. 

KTVU meteorologists said that will be the theme of this atmospheric river through Friday morning when the storm system moves south to San Jose and Morgan Hill. 

Lake Tahoe

The Lake Tahoe area is also facing storm conditions this week with a winter storm warning and lake wind advisory. 

UC Berkeley's Central Sierra Snow Lab is estimating 3 ½ to 7 feet of snow over the next 10 days. The snow lab said Thursday that 10 to 20 inches of snowfall is likely by Friday morning. 

The Sierra saw its first snow of the season in mid-October with precipitation in Soda Springs, the snow lab reported. 

Several Lake Tahoe ski resorts are opening later this week and in early December as snowfall begins.