An atmospheric river storm that is expected to drench the Bay Area and Central Coast starting Tuesday night will bring more rain than was earlier anticipated forecasters say, raising the risk of power outages, downed trees and potentially deadly mudslides in the days ahead — with evacuation orders for an estimated 5,000 people in the Santa Cruz Mountains announced Monday.
The National Weather Service said that as the storm has moved closer, revised forecasts call for it to dump 3 to 5 inches of rain on Bay Area cities, mostly Wednesday and Thursday; 5 to 8 inches at higher elevations; up to 10 inches in some parts of the Santa Cruz Mountains and up to 13 inches in Big Sur. B
“There’s going to be a lot more moisture than we had thought,” said Matt Mehle, a meteorologist with the National Weather Service in Monterey. “It’s been quite some time since we’ve seen a storm like this.”
On Monday morning, Cal Fire and sheriff’s officials in Santa Cruz County issued evacuation orders for 2,800 homes with nearly 5,000 residents in parts of Felton, Ben Lomond, Brookdale, Boulder Creek, the Swanton area north of Davenport along Highway 1, and other rural communities in the Santa Cruz Mountains where the CZU Lightning Complex Fire burned 86,509 acres last August, destroying 1,490 buildings, including homes and businesses from Bonny Doon to Big Basin Redwoods State Park.
“We ask you to heed these warnings and get out of the way,” said Ian Larkin, chief of Cal Fire’s San Mateo-Santa Cruz Unit. “You will not hear a debris flow. When it occurs, if you hear it, it is too late.”
The orders were posted on a county map at https://community.zonehaven.com/
People who evacuate probably will be able to return by this weekend, he said. Santa Cruz County set up temporary emergency access points at three locations: San Lorenzo Valley High School in Felton, Pacific Elementary School in Davenport and Scotts Valley Community Center, at 360 Kings Village Road in Scotts Valley. Bathrooms, charging stations, food and Red Cross workers will be available.
Homes near steep slopes that burned are most at risk from debris flows, commonly called mudslides, which can send thousands of tons of soil, trees, rocks and other debris down hills in seconds, said Jason Hoppin, a spokesman for Santa Cruz County. On Monday, 31 sheriff’s deputies fanned out across the Santa Cruz Mountains, knocking on doors and telling people in danger zones to leave.
“This is a storm we were hoping we weren’t going to see, but we are potentially going to see,” said Chris Clark, chief deputy sheriff in Santa Cruz County. “Make sure you are as safe as you can be. I couldn’t stress more the need to follow the evacuation order.”
The area knows deadly mudslides firsthand. On Jan. 5, 1982, following torrential rains, a steep hillside collapsed at Love Creek, a tributary of the San Lorenzo River in the redwoods near Ben Lomond. The horrific slide destroyed 30 houses, killing 10 people. Four victims, including two children, were never found and remain buried there.
“People do remember Love Creek,” Hoppin said. “As tragic as it was, it will hopefully serve as a lesson now to prevent something similar from happening again.”
Three years ago, in Montecito, near Santa Barbara, a mudslide one month after the Thomas Fire killed 23 people and destroyed 65 homes.
The National Weather Service, working with geologists from the U.S. Geological Survey, estimated that a quarter inch of rain in 15 minutes, or half an inch in 30 minutes, is enough to trigger mudslides in the burned areas of the Santa Cruz Mountains. The weather service issued a flash flood warning for Tuesday afternoon through Thursday afternoon for the North Bay, Santa Cruz Mountains and Big Sur, saying there is “high confidence” that rain levels will exceed mudslide danger thresholds.
Daniel Baric, who lives along Jamison Creek Road between downtown Boulder Creek and Big Basin, said Monday afternoon that his wife and two sons were packing important documents, clothes, their dog, cat, a turtle and pet gecko to move to a hotel in Santa Cruz. Flames from the wildfire burned their backyard sheds and fences. Firefighters barely saved their home. In 15 years of living in the mountains he’s never seen a year like this past one.
“It’s definitely not easy,” he said stoically. “But we’re ready to go. We’re keeping our heads. We’re all alive. That’s the number one thing. People are all helping each other. We’ll make it.”
Meanwhile, across the wider Bay Area, flooded roads and power outages are likely. Winds Tuesday night into Wednesday will be 40-50 mph with gusts as high as 65-70 mph over higher peaks in the Bay Area, forecasters said.
Driving it all is an atmospheric river storm. Such moisture-rich storms — which can end droughts, and bring massive amounts of snow, but also cause floods and mudslides — often come from Hawaii. Then, they are called “Pineapple express storms.”
This storm, however, is not a Pineapple express. It is looping in an unusual pattern from south of Hawaii, around a high-pressure zone in the north Pacific past the Aleutian Islands in Alaska, then charging down the West Coast before the brunt is expected to come ashore in the Monterey Bay area. There is increasing concern it will pass through the Bay Area, then surge over Big Sur and the Santa Cruz Mountains a second time, according to computer models.
Unless something changes significantly, the storm will bring more rain to the Bay Area in 24 hours than any storm in at least 12 months, and possibly three years or more. It also is forecast to bring up to 7 feet of new snow to the Sierra Nevada, closing highways Wednesday and possibly Thursday, forecasters said.
California is in dire need of precipitation, following months of dry, sunny weather. After light rains Sunday, San Jose was at just 17% of its historical rainfall average for this date. Oakland was at 22% and San Francisco at 27%. The storm is expected to move all three cities to about 50% of normal, perhaps slightly more. The Sierra Nevada snowpack, the source of one-third of California’s water supply, was at just 40% of normal Monday. The new snow will send that total significantly higher.
More rain is expected Friday, forecasters said. Much more is needed in February and March to boost reservoirs, groundwater tables and moisture levels in plants to reduce fire risk next summer.
“The high pressure that was sitting over us on the West Coast shifted west,” said Mehle. “That allowed the jet stream to shift so it could come south. And now the storm door is open.”
“The rain will be a welcome sight when it comes to our water supply,” he added. “But we need a considerable amount of rain to get back to normal. We aren’t going to erase the deficit with one event.”
Contributed by local news sources