SAN FRANCISCO (KGO) -- A powerful atmospheric river is taking aim at the San Francisco Bay Area, bringing with it the threat of severe flooding, heavy rain and gusty winds.
The first of a series of storms arrives Thursday and ranks a Level 3 on the exclusive ABC7 Storm Impact Scale.
RELATED: Here's what to expect for Level 3 storm Thursday and Friday
Governor Newsom declares storm state of emergency supporting 21 additional counties
Governor Gavin Newsom announced a state of emergency Wednesday to help California counties ahead of a severe winter storm this week.
The latest proclamation will help with disaster response and relief for 21 counties, including San Francisco, Santa Clara, Santa Cruz and Monterey counties.
The state will be using all available resources to help residents impacted by the storm.
Road to Mt. Hamilton summit could reopen by Friday, Caltrans says
The snow covered summit of Mount Hamilton is home to about 30 resident staffers of the Lick Observatory. The peak was pummeled with a record amount of snow over several recent storms.
"Right now, we're still overwhelmed with snow. The official snow tally as of yesterday, since February 22, is 53 inches of snow on Mt. Hamilton," resident astronomer Dr. Elinor Gates said.
Thursday's incoming storm is creating additional concern, especially with strong winds and intense rain expected.
"We still have snow and ice in the way. So where's that water going to go? It's going to flood through our plowed drives and walkways. We might have ice dams, so it might end up going underneath shingles and leaking into houses."
She also points to the possibility of ice and snow sliding from the observatory's domes. It's movement that could be dangerous for anyone or anything below.
Still, resident astronomer Dr. Paul Lynam says there is some welcome news, including warmer temperatures and better timing.
"Not in the immediate aftermath of the 2020 SCU Complex Fire, which left a lot of burn scars," he described. "At least we've had a season or two for the ground to recover and some of the vegetation to regrow. That will hopefully minimize those slippages, those rock slides and mudslides potentially."
Currently, the road to the observatory has been closed to the public for weeks, with barricades manned by law enforcement. One passable lane has allowed emergency and maintenance vehicles, and resident staffers to venture up and down the mountain. Caltrans crews and others have been working around the clock to clear the roadway.
"The next two days the road could still be treacherous not necessarily through the snow but just by flooding, mudslides, rockslides and downed trees," Dr. Lynam said.
Dr. Gates added, "It wouldn't be surprising, in our remote location, to lose power for maybe many days again. But our generator, with the full diesel tank, we can go for about a week."
Caltrans officials said they're monitoring conditions. Ahead of the storm, they're working to clear ditches to prevent flooding, watching for downed trees, and looking out for slides.
"Since we've been looking and monitoring the weather forecasts, and with all the cleaning that we've been doing, we're looking forward to being open by Friday," Caltrans PIO for Santa Clara County Victor Gauthier said.
Danville residents prepare for more potential flooding
One neighbor could be seen moving her vehicle to higher ground. Everyone with vivid memories of El Capitan Drive flowing with water a couple of months ago.
"There was so much water coming down the street. There was actually an SUV floating down the street," said Danville resident Dia Mundle.
The neighborhood was hit especially hard during that atmospheric river as we began 2023, now another one is on the way.
"I think everybody in the neighborhood feels probably like the worst is over but now it looks like it may start all over again," said John Hughes of Danville.
John Hughes just finished redoing his front yard that was destroyed by all the mud from that storm, and now here we go again.
"It was really kind of scary. We had to be evacuated," said Hughes.
His family evacuated out their back door but both their cars that had been parked in their driveway were eventually totaled.
"We've been here since '75 and nothing close to it," said Hughes.
As to how those in the neighborhood are preparing now. Sandbags can be seen at at least two different houses, streets are now clear, and homes are working.
No chains required yet on I-80 and Highway 50 to Tahoe
There are no chain requirements in effect for either I-80 or Highway 50 heading to Tahoe as of Wednesday evening.
For the latest on road conditions, visit here.
Valley Water prepares in hopes to avoid flooding with 1st atmospheric river since Jan.
With an atmospheric river heading towards the Bay Area again, Valley Water is gearing up in hopes to avoid a repeat of January's storm. The Southern part of Santa Clara County is expected to get the most rain. Places like Morgan Hill and Gilroy saw serious flooding at the start of the year as well, so Valley Water has crews spreading out across the region to keep waters flowing.
"We hope that it's not going to be as bad, but in January, that one wasn't forecasted to be bad and it kind of just stalled over us," Valley Water spokesperson Meghan Azralon said. "So, we're taking those same precautions just in case. There's always a possibility that mother nature changes her mind."
Valley Water is also hard at work filling up sandbag locations across the South Bay as well. 4,200 bags were dropped off and quickly loaded up in Morgan Hill. Areas south of the county are forecasted to get more than two inches of rain leaving creek and stream flooding risks high.
Familiar with the risks that heavy rainfall can create, it's a constant state of preparation for some residents. They say when you see rain in the forecast, you don't get ready, you stay ready.
Danville issues storm safety advisory ahead of storm
Danville issued a storm safety advisory Wednesday afternoon, warning residents to be ready for wet weather that will likely start Thursday morning.
Town officials say the three main areas of concern are rain and increased winds generating flooding, downed trees, and loss of power. They ask residents to avoid unnecessary travel during the storms and, if they do drive, to avoid driving through flooded intersections.
They also ask residents to remove leaves or debris blocking storm drains to allow stormwater to flow through unobstructed into the stormwater system. Danville will offer a self-fill sandbag station for community use at 1000 Sherburne Hills Road. They ask residents to limit use to 20 sandbags per household.
To report clogged storm drains, downed trees, or flooding, call Danville maintenance services at (925) 314-3450, or after hours contact non-emergency dispatch at (925) 820-2144. Residents can also make reports online.
Vallejo warming shelter opens Thursday
The city of Vallejo is opening a warming shelter beginning Thursday in anticipation of extreme weather headed to the region.
The warming shelter will be open from 8 p.m. to 7 a.m. Thursday, Friday and Saturday at 505 Santa Clara St. on the backside of City Hall.
A limited number of blankets and pillows will be available, but participants are encouraged to bring their own. One small bag of personal items is also permitted.
Those seeking transportation to the shelter can get a free bus ride on SolTrans public transit by simply mentioning to the bus driver that they are traveling to or from the Vallejo warming shelter, a spokesperson for the city said.
RELATED: Yosemite National Park braces for flooding ahead of atmospheric river storm
Oakland urges residents to call 311 to report downed trees, flooding
Wind and lots of rain are expected in Oakland starting Thursday morning and city officials urge residents to prepare and even volunteer to prevent flooding.
Emergencies such as downed trees or limbs can be reported by calling 311 or (510) 615-5566. If it's challenging to get a hold of someone by calling 311, residents can call the Oakland Fire Department's non-emergency line at (510) 444-3322.
Other emergencies that can be reported to 311 include flooding, overflowing sewers and street signals that aren't working. Non-emergencies can be reported online.
City officials are asking residents to adopt a drain in their neighborhood to help prevent flooding. Public works crews are clearing storm inlets and many residents have adopted a drain, but many thousands of drains remain available for adoption. The city can give residents supplies such as rakes, brooms, dust pans, and bags.
Call (510) 238-7630 or go to the adopt-a-drain website to sign up.
Up to 10 free sandbags and up to 20 feet of plastic sheeting are available to each Oakland household while supplies last. Pick them up at the Municipal Service Center at 7101 Edgewater Drive Monday through Friday from 8 a.m. to 4 p.m. and Saturdays and Sundays from 8 a.m. to 4:30 p.m.
Monterey Co. distributing sandbags ahead of storm
Residents in unincorporated areas of Monterey County can pick up sandbags at several locations in the county ahead of another storm forecast to hit the Central Coast on Thursday and Friday.
Empty sandbags can be picked up at the following Cal Fire stations: Aromas, Big Sur, Cachagua, Cypress, Carmel Highlands and Greenfield, as well as stations in the North County Fire Protection District.
A complete list of sandbag locations can be found here. Bags can be filled at these locations.
For questions about sandbags, contact the Monterey County Public Works maintenance office at (831) 755-4925.
Residents in incorporated areas can pick up and fill bags at Fire Stations 11, 12 and 13 in the city of Monterey, the Vista Lobos community center in Carmel-by-the-Sea, and the Pacific Grove fire station.
RELATED: Is 2023 Bay Area's worst storm season? Here's what experts say
Winter Storm Watch to effect Thursday for Sierra Nevada
A Winter Storm Watch will be in effect Thursday through Sunday for heavy snow and gusty winds. Snow levels will be high, above 6,500 feet (that is roughly the elevation of Soda Springs on I-80, Phillips on Highway 50) where two to five feet of snow will fall. Gusts up to 80 mph are expected.
Flood Watch in effect from Thursday-Sunday for entire Bay Area
A Flood Watch is in effect from Thursday through Sunday for the entire Bay Area and the Central Coast. Lingering rain will continue into the weekend with additional widespread rainfall expected next week.
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Bay City News contributed to this report.
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