A powerful storm rolled into the Bay Area on Wednesday, bringing with it the potential for widespread flooding, damaging winds and other severe impacts.

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By mid-morning, thousands of residents had already lost power. Dozens of flights were canceled or delayed. Evacuation orders were issued. Schools, parks and roads were closed, while Gov. Gavin Newsom declared a state of emergency and officials scrambled to help the homeless across the Bay Area.

Rain, while milder in the early morning, picked up by the evening.

San Jose is slated to receive three-quarters of an inch of precipitation, Oakland up to one inch, and San Francisco between one and two inches. Strong thunderstorms are a possibility by Wednesday night, according to the National Weather Service.

“The storm we have been waiting for is here,” Mary Ellen Carroll, executive director of San Francisco’s Department of Emergency Management said around 5:20 p.m. at a news conference.

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Flood warning issued for Monterey County, 7 p.m.

The National Weather Service on Wednesday night issued a flood warning for Monterey County. The warning took effect around 5:40 p.m. and will run through 11:45 p.m.

Flooding is expected in areas including Carmel-By-The-Sea, Marina, Monterey, Seaside and Julia Pfeiffer Burns State Park.

“Flooding of rivers, creeks, streams, and other low-lying and flood-prone locations is imminent or occurring,” the county’s Office of Emergency Services said in an advisory.

The office urged motorists to avoid flooded roadways, noting that most flood deaths occur in vehicles.

The NWS also issued a flash flood warning for the Big Sur coast, including the Colorado and Dolan burn scars. The warning will run through 12:15 a.m. Thursday.

Mandatory evacuation order issued in Rio del Mar, 6:30 p.m.:

Rio del Mar sisters-in-law Mary and Maureen Sztenderowicz, both in their 70s, were obeying a mandatory evacuation order issued Wednesday Afternoon by the Santa Cruz County Sheriff’s Office, for low-lying areas of the beachside town just down the coast from Santa Cruz, where Aptos Creek meets the ocean.

“We don’t want to be stuck and not able to get out,” Mary said.

Maureen added, “Health issues are another factor.”

The two planned to stay for a night or two with a relative in Santa Cruz.

But Theresa Hosking, 71, said she planned to ride out the storm from her Rio del Mar home near the beach and Aptos Creek.

“I’m not worried,” said Hosking, who lives with her adopted grandsons, 16 and 17. “If it starts getting bad I only have maybe a quarter of a mile to walk to get out of the flood.”

Hosking said she had her important documents in two storage containers, and if she has to flee with her grandsons, they’ll grab their dog, the containers and her phone.

Santa Cruz County Sheriff’s Office deputies were posting red evacuation orders outside homes in the Rio del Mar flatlands Wednesday afternoon. “We’re not going to make people leave,” said Deputy Ryan York. Instead, deputies are telling people that if they don’t evacuate, they may not be able to get help in case of emergency, York said.

Of primary concern was Aptos Creek, York said. Although the waterway was not raging Wednesday afternoon, ocean swells and tides — both forecasted to be very high Wednesday night and Thursday morning, according to the National Oceanic and Atmospheric Administration — are expected to surge in, and by blocking outflow of stream water, raise the creek’s level even higher, York said.

–Ethan Baron

Residents head for higher ground in Soquel, 6 p.m.:

Low areas of Soquel, near Santa Cruz, that suffered severe flooding over the weekend, were put under a mandatory evacuation order Wednesday afternoon.

Lori Wilson, a 62-year-old retired art teacher, was heading for higher ground at a friend’s place Wednesday afternoon with her cat, Luna, in the car. Although floodwaters from a raging Soquel Creek had muddied her patio on the weekend, she was more worried about trees falling on her home in what is expected to be a bigger storm Wednesday night and Thursday, she said.

“The trees were really snapping and cracking the other night,” Wilson said.

–Ethan Baron

Fremont opens emergency storm shelter, 5:30 p.m.

The city of Fremont on Wednesday opened an emergency shelter at Washington High School.

Located at 38442 Fremont Boulevard, the shelter inside the school’s small gymnasium will remain open through Friday, police said in an advisory. Warm meals, beverages and face masks will be supplied.

Service animals and pets are welcome at the shelter. All animals except ADA service animals will be kenneled on-site with food and water, according to the advisory.

For more information, contact Fremont Human Services at 510-574-2050 or [email protected].

Santa Clara County closes roads, 5:15 p.m.:

The following roads in Santa Clara County were closed because of the storm, the county’s Office of Emergency Operations said in a news release late Wednesday afternoon.

• Calaveras Road from Felter Road to the Alameda County line
• Mines Road from Del Puerto Road to the Alameda County line (washouts)
• Sierra Road from Skyview Drive to Felter Road due (slides and storm debris)
• Stevens Canyon Road between Mt. Eden Road and Redwood Gulch Road (downed tree and communication line)
• Mesa Road from Santa Teresa Boulevard to Highway 101 (flooding)
• Gilroy Hot Springs Road at Coyote Reservoir (flooding)
• Bloomfield Avenue between Frazier Lake Road and Highway 152 (flooding)
• Mt. Madonna Road from 1.75 miles east of Redwood Retreat Road to Summit Road in Gilroy.

The office urged drivers to be alert for road closure signs as well as equipment and crews.

Emergency road closure information is available here.

Heavy rain moves into Bay Area, 4:30 p.m.:

Heavy rain entered the Bay Area around 4:20 p.m., according to a radar update shared by the NWS. Roughly an hour later, the agency also shared data showing gusts up to 85 mph in Marin.

Radar Update 4:21 PM – Heavy rain now entering the Bay Area. #cawx. pic.twitter.com/WM7awylGUF

— NWS Bay Area (@NWSBayArea) January 5, 2023

Impressive wind showing up in Marin. Gusts up to 85 mph now (4:10-4:30)! #cawx pic.twitter.com/D2VSUN768s

— NWS Bay Area (@NWSBayArea) January 5, 2023

Check back for updates.