AccuWeather is wrapping up live coverage of the deadly storm that brought high wids, drenching rain and snow throughout California. AccuWeather meteorologists are now warning about another storm that will impact the state next week. For additional coverage, stream AccuWeather NOW anytime on our website. Stay up to date on the latest weather in your area by downloading the AccuWeather mobile app and visiting AccuWeather.com. And keep an eye on weather news and forecasts by following AccuWeather on:
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Utility crews in the Bay Area were hard at work in dangerous conditions Tuesday, clearing downed trees in Boulder Creek, roughly 40 miles southwest of San Jose. Those in Boulder Creek worked amid downed power lines, heavy downpours and wind gusts over 70 mph. “If you live in the mountains, every 10 years or so [a storm is] going to be hard,” Boulder Creek resident Tyrone Clark told Reuters. “Sometimes, really hard.”
The area also experienced mudslides Tuesday, with Clark noting this is his first encounter with them in his 20 years in the area. “I’ve never seen it, and it’s just a lot of rain,” Clark said. “Sometimes there’s drought and sometimes there’s lots of rain. I think in the [1990s] we had [storms] that were like this, but I think the trees are just bigger now and [are] not handling the weight.” An evacuation order was issued for a short time in a section of Boulder Creek Tuesday, due to a blockage in a local creek rising water levels.
Crews were busy cleaning up downed trees across roadways near Boulder Creek, California, on March 21.
A likely tornado struck east of downtown Los Angeles Wednesday, damaging multiple buildings in Montebello, California. The Verdugo Fire Communications Center classified the likely tornado as a “weather incident” that was reported just a few minutes before 11:30 a.m. PDT. KTLA reported that part of a local roof was ripped off and debris was thrown around the area. No injuries have been reported so far, and the National Weather Service confirmed it will investigate the incident further. Video sent to KTLA showed a funnel cloud in the area, creating an eerie atmosphere for Montebello residents.
Despite the storms, drivers in Temescal Valley, California, tested flooded roads on Tuesday, resulting in a mess of a situation. Heavy rain and flooding caused problems for many, as video showed motorists trying to get around particularly drenched spots of the road. One car was seen stranded, with muddy waters running rapidly around the vehicle. On top of the flooding, high wind gusts were also a concern, as Riverside County valleys such as Temescal were under a wind advisory throughout Tuesday.
Heavy rain and flooding has caused travel issues for many motorists in Temescal Valley, California, including one who was left stranded on March 21. At least one fatality was reported from the storms.
East Oakland resident Yan Hui Zuo had been trying to take a nap when a tree came crashing down into her bedroom on Tuesday afternoon. “The tree went straight like this,” Zuo told KTVU Fox 2, adding it had landed on her desk. Two of the six eucalyptus trees next to her home had fallen and severely damaged the building. Concerned the roof would collapse, she searched for her dog before crawling out her bedroom window. She escaped with minor injuries, KTVU Fox 2 reported.
The situation could have been prevented, however, according to members of her family. The city of Oakland had asked the family’s permission to cut the trees down two years earlier, Brian Tuyen, Zuo’s cousin told the local news station. The family had consented, but the city never followed through. “Our lives are in danger here. We know there’s an issue. The city knows about it,” Tuyen said. “Let’s get things done.”
Officials and emergency crews across California are hard at work responding to the latest storm to slam into the Golden State. “We’re continuing to mobilize an all-hands-on-deck response to protect Californians during this latest round of devastating storms,” Gov. Gavin Newsom said. “The state is working closely with federal and local partners to provide immediate relief and support the ongoing recovery.” More than 470,000 sandbags and 488,000 square feet of plastic sheeting were distributed across the state to help residents stave off floodwaters. Additionally, over 4,000 Caltrans employees are working across the state to respond to emergencies on the roads. State officials are also conducting damage assessments to determine if California meets the federal government’s criteria for a major disaster declaration.
The bomb cyclone that slammed California brought intense wind and rainfall to the state, including the Bay Area. “The impacts from the event resembled that of a landfalling strong tropical storm – likely the closest San Francisco residents will ever come to experiencing that meteorological phenomenon,” AccuWeather Director of Forecast Operations Dan DePodwin said. Peak gusts in the higher elevations immediately around the Bay Area exceeded 70 mph on Tuesday, according to preliminary reports from the National Weather Service. One of the highest preliminary wind reports Tuesday listed by the National Weather Service’s Storm Prediction Center was a 75 mph gust recorded near Lexington Hills in Santa Clara County. A gust of 73 mph was recorded near Del Rey Oaks in Monterey County.
“Tropical-storm-force wind gusts (39-73 mph) were reported for seven consecutive hours in Oakland,” DePodwin said. “Despite being vastly different in structure than a tropical system, the compact area of low pressure on radar resembled the eye of a hurricane as it moved onshore Tuesday afternoon just south of San Francisco.” Some of the greatest rainfall totals in the Bay Area were recorded in the Santa Cruz Mountains as well as cross portions of the North Bay. Some of the hardest-hit areas received 3-4 inches of rainfall, according to preliminary numbers from the NWS.
Numerous roads in Santa Cruz County were impassable and strewn with debris on Wednesday morning following intense wind and rain on Tuesday. The California Highway Patrol warned people of closed roads across the county due to downed trees, power lines and flooding. “Please don’t drive across or under downed trees, branches, and/or wires,” officials said in a post on Twitter. The coast and mountains just south of the Bay Area were the hardest hit by the storm on Tuesday as the storm’s center roared ashore. Roughly two-thirds of all power outages in California were in Santa Cruz, San Mateo, Santa Clara and Alameda counties, according to PowerOutage.us.
California has been bombarded by atmospheric rivers, bomb cyclones and a few pineapple expresses in recent months making for one of the stormiest winters in recent history. The rainfall total at one weather station in the Southern Coast Ranges reached new heights amid the ongoing storm. Three Peaks, located in the mountains about 100 miles southeast of San Jose, has measured 101.45 inches of rain since Nov. 1, 2022, according to the National Weather Service office in the Bay Area. The weather station on the mountain is at an elevation of 3,362 feet, with the elevation contributing to the extraordinary seasonal rainfall total as higher rainfall amounts are common in the mountains compared to the lower elevations.

A skier walks between mounds of snow engulfing houses as heavy snow continues in the first days of spring on March 21, 2023 in Mammoth Lakes, California. (Photo by David McNew/Getty Images)
Mammoth Mountain, located in the central Sierra Nevada, is having a ski season for the ages. With a total of 664 inches of snow so far this season, it has more than enough to stay open through the spring. But officials at the resort aren’t content with spring skiing. They plan to remain open well into the summer.
“We are stoked to announce that we will be open daily for skiing and riding until AT LEAST the end of July,” the resort stated in a Facebook post on Tuesday. “As always, we do not have a closing date set, but will plan to stay open as long as conditions allow. Sitting on one of the deepest base depths ever recorded at Main Lodge, it’s going to be some of the best spring skiing and riding we’ve ever seen.”
The mountain had received 18-20 inches of new snow as of Wednesday morning from the latest storm that moved through. Mammoth is now 5 inches of snow away from breaking its all-time seasonal record of 668 inches.

A worker shovels snow from a roof at the Shilo Inn as it continues to deepen in the first days of spring on March 21, 2023 in Mammoth Lakes, California. (Photo by David McNew/Getty Images)
The storm that crashed into the central California coast on Tuesday afternoon underwent bombogenesis, a meteorological process more commonly known on social media as a bomb cyclone. For a storm to be dubbed a bomb cyclone, the atmospheric pressure must drop at least 0.71 of an inch of mercury (24 millibars) in 24 hours. Tuesday’s storm blew this benchmark out of the water with a buoy in Monterey Bay, just south of Santa Cruz, recoding a pressure drop of 0.71 of an inch of mercury (24 millibars) in just 17 hours. The storm’s ferocity also generated a storm surge of two feet along the coast of central California. The storm was so intense that it appeared to develop an eye on satellite, similar to what is seen in tropical storms and hurricanes, although this week’s storm was much different than a tropical system.
An Amtrak train derailed Tuesday afternoon after striking a downed tree near Port Costa, California, in Contra Costa County, officials reported. There were no immediate reports of injuries and a total of 55 passengers and crew were onboard at the time of the accident, according to the Crockett-Carquinez Fire Department which responded to the incident. The train had remained upright through the collision, and all systems were still operating, ABC 7 News reported.

Fire crews respond to the derailment of an Amtrak train in Port Costa, California, during the heavy rainstorm that hit the state Tuesday. No one was injured in the incident, according to authorities. (Crockett-Carquinez Fire Department)
At least two deaths were reported on Tuesday due to trees falling on vehicles in California. According to The Associated Press, a man was killed when a tree toppled onto the sewer truck he was driving near the community of Portola Valley, located in the Bay Area. The second deadly incident occurred in the Southern California community of Rossmoor. A passenger was killed and the driver was injured, the Contra Costa County Fire Protection District said, according to the AP.
In less than two hours over the course of Tuesday afternoon, almost 50 spotter reports of wind damage, mostly downed power lines and trees down in roadways, were submitted to the National Weather Service. Most of the reports were within 30 miles of Santa Cruz, California. During that time, a weather station north of Santa Clara at Mount Alison recorded a gust of 81 mph, while another station measured a 75 mph gust in the mountains to the south of San Jose near Lexington Hills.
Editor's Note: This post has been updated with additional information from The Associated Press.
Although the statewide number of electrical customers without power was lower on Wednesday compared to Tuesday, it was still high. PowerOutage.US reported that more than 130,000 were without power in the state following Tuesday’s high winds and rain. At one point on Tuesday, that figure was nearly 250,000. The majority of the outages belonged to Pacific Gas & Electric. Nearly 113,000 PG&E customers were without electricity Wednesday morning, according to PowerOutage.US.

The worst of the storm in California was mostly on Tuesday, although AccuWeather forecasters caution there will be some more rain and snow in the state on Wednesday. The storm that walloped the Golden State with high winds, flooding rain and heavy snow is impacting more of the Southwest on Wednesday. Heavy rain could cause flash flooding concerns in cities such as Phoenix and Las Vegas, while up to a foot of snow could fall in Flagstaff, Arizona. Elsewhere, Denver is expected to be targeted by the storm as well, but meteorologists say only a few rain showers are anticipated there from Wednesday to Thursday.

The long-term drought continues to be trimmed in California. However, the heavy rain has caused flooding and flood advisories and flood watches remain in effect. The focus will largely shift to Southern California on Wednesday. Downtown Los Angeles received 1.43 inches of rain on Tuesday, breaking a 130-year-old record for March 21. Some of the higher elevations, below snow level, received 4 to 5 inches of rain on Tuesday. The storm should finally wind down later on Wednesday.

California rainfall totals as of 11 p.m. PDT Tuesday
The latest round of California storms has worsened conditions for animals trapped by several feet of snow in the state. Recent video showed members of the California National Guard delivering emergency hay to starving cattle in snow-covered areas, as cattle have been struggling to eat grass that has been buried by the feet of snow that has accumulated. The concern is also growing for animals on the eastern side of Montana, which has also seen above-average snowfall.
Volunteers from the Buffalo Field Campaign were recently seen working with the Montana Department of Transportation to shovel snow on roadways, in order to carve a path for the area’s buffalo population. “In the next probably month or so, we are going to have a migration of anywhere from 3-700 buffalo,” Buffalo Field Campaign Co-Founder Mike Mease told AccuWeather. “Unfortunately, right in the middle of that corridor to get to where they need to go lies Highway 191, and 191 currently has 6-foot snow [piles] along the entire highway.”
The California National Guard and the Montana Department of Transportation have assisted with helping animals stranded by heavy snow in the western half of the U.S.
The San Bernardino Mountains have been slammed by snowfall in recent months, and residents are still feeling the impacts heading into this week’s storm. Lake Arrowhead, California, resident Lisa Griggs told AccuWeather that “it’s going to be interesting how people pull through” the storm after rounds of powerful snowstorms from late February into early March left at least 13 people dead and communities cut off.
“It’s been devastating on our community,” Griggs said. “It’s really hard, we’re watching our community just pull together but also just take hit after hit after hit. Quite honestly, after this last storm, we just thought there wasn’t going to be anything more.” Griggs noted that there is still much snow to clear, with some residents still trapped in their homes. She also said that food shortage may become a greater issue with only one grocery store in the area. The AccuWeather WinterCast for Lake Arrowhead forecasts a strong chance of the area picking up another 4-8 inches of snow by 10 p.m., PDT Wednesday.
Lake Arrowhead, California, resident Lisa Griggs shares how her community is struggling to dig out of the effects of recent winter storms with more snow heading towards the area this week.
One of Lake Tahoe’s largest winter sports resorts will keep locals and travelers on the slopes a while longer. Heavenly Ski Resort announced Tuesday that its ski and ride season will be extended through May 7, with the resort thanking crew members for “keeping up with all the storms so we can keep sliding around on snow.” The resort picked up another 8 inches of snow over the past 48 hours, adding to an impressive seasonal snowfall total of 538 inches. Conditions at the resort will feature gusty winds for the remainder of the week, with high temperatures between the teens and low 20s.
After being closed for weeks, one of California’s most popular parks is now slowly reopening. Yosemite National Park was a victim of February’s storm onslaught in the state, with snow piling as high as 15 feet in some areas. “It just wasn’t safe to welcome visitors,” National Park Service ranger Scott Gediman told AccuWeather National Reporter Emmy Victor. Since that time, crews have been hard at work digging out snow, as well as repairing both roads and facilities impacted by snow and rockslides. Park officials documented 22 rockslides, debris flows and other slope failures along park roads during the repair period.
Now reopened with limited hiking trails and lodging services, the park can once again welcome visitors, including Brazil resident Felipe Richachenevsky. “We don’t have snow back home, this is not a common thing for us,” Richachenevsky told Victor, finding alternate lodging at the park after his original housing was deemed unavailable. “So even getting a tiny bit of snow on the ground, it’s very unusual where we live.” Gediman noted that the snowfall will lead to a gorgeous spring season, particularly for the park’s waterfalls.
Park officials say the park is open at limited capacity starting March 20.
Classes for Los Angeles public schools were canceled Tuesday for just the second time in five years, but not due to the rainfall that has continued to drench the city. Tens of thousands of service workers, joined by Los Angeles Unified School District teachers, went on the first day of a proposed three-day strike Tuesday, standing outside the closed doors of the Edward R. Roybal Learning Center with raincoats and umbrellas at the ready. Members of the Service Employees International Union Local 99, which includes custodians, cafeteria workers and bus drivers, walked off the job after negotiations with the Los Angeles Unified School District came to a halt.
The service employees union, which boasts 30,000 members, is demanding higher wages and improved working conditions. The United Teachers Los Angeles Union honored the service union’s picket lines Tuesday, forcing schools to close for more than 500,000 Los Angeles public school students. “We stand in solidarity with them, recognizing that their struggles are our struggles … that the only way we achieve our goals is by standing collectively together,” United Teachers Los Angeles Union President Cecily Myart-Cruz said. Los Angeles Mayor Karen Bass said that the city will be making recreation centers available for students during the strike, and the Los Angeles Zoo will offer free admission to students during the strike period as well.

Los Angeles Unified School District, LAUSD teachers and Service Employees International Union 99 (SEIU) members strike during heavy rain outside the Edward R. Roybal Learning Center in Los Angeles Tuesday, March 21, 2023. Tens of thousands of workers in the Los Angeles Unified School District walked off the job Tuesday over stalled contract talks, and they were joined by teachers in a three-day strike that shut down the nation’s second-largest school system. (AP Photo/Damian Dovarganes)
A top university in the Bay Area was forced to alter its schedule Tuesday due to power outages that have deeply impacted the region. At Stanford University, a mass outage was caused due to one of the main transmission lines feeding the campus being impacted by storms, with no estimated time of restoration as of 5:30 p.m. PDT. University officials announced that exams scheduled for the remainder of Tuesday have been canceled, stating that the outage “presents a very unusual circumstance for both our students and faculty.” Santa Clara County, where Stanford's campus is located, had over 21,000 power outages as of 5:30 p.m. PDT, according to PowerOutage.US.
Gusty storms in San Francisco have hampered air travel in the area, with nearly 100 cancellations and hundreds of delays reported at San Francisco International Airport. A ground stop was issued Tuesday afternoon for the airport through 5:30 p.m. PDT, and the airport remains under a ground delay through 12:59 a.m. PDT Wednesday. The average delay, cited due to high winds, was 253 minutes, or over four hours, as of early Tuesday evening. According to flight tracking site FlightAware, 184 departing flights and 219 arrivals have been delayed so far at the airport Tuesday. Another 50 departures and 35 arrivals were canceled.
Sequoia and Kings Canyon National Parks have been buried by heavy snow in recent weeks, although the deepest snow piles still pale in comparison to the massive sequoia trees that grow in the Sierra Nevada. The parks are located in the southern extent of the Sierra Nevada, and at an elevation of over 6,000 feet, they are once again facing heavy snow. “Crews have spent the last few days prepping for this weather event,” the parks said in a Twitter post. “Cross your fingers for us that we won’t sustain much new damage!” People have been hard at work digging out from the last storm, but they have also been using sandbags to prevent melting snow from flooding buildings in the mountains. AccuWeather meteorologists are predicting several more feet of snow in the national parks through Wednesday.
Wind gusts have remained incredibly strong in California throughout Tuesday, including multiple reports of gusts topping 100 mph. The highest wind gust reports came from the Central Coast and Los Angeles areas of the state, including a 118 mph gust recorded at Hopper Canyon, just outside of San Bernardino. Other wind gusts besting 100 mph were at San Guillermo Mountain (105 mph) and Magic Mountain (102 mph). In Loma Prieta, roughly 20 miles south of San Jose, gusts reached 89 mph, nearly beating a top gust of 97 mph in the area during last week’s storms. In the Southern Coast and San Diego areas, the top wind gusts were reported in Boucher Hill (65 mph) and Harrison Park (60 mph).

First responders in San Bernardino County jumped into action Tuesday by making a water rescue during the morning hours. Firefighters and paramedics were called in around 11:40 a.m. PDT after a vehicle reportedly tried to cross high water before it was swept away in the current northwest of San Bernardino. The sole occupant of the vehicle self-extricated to make it to dry ground, and responders made contact after finding an access route. The victim was being evaluated and treated for hypothermia as of 12:26 p.m. PDT.
Power outages have skyrocketed in California into the afternoon hours Tuesday, with nearly 250,000 customers without power as of 5 p.m. PDT, according to PowerOutage.US. The number is a huge jump from 8 a.m. PDT, when outages in the state totaled 9,000. The Bay Area, where winds have been particularly gusty throughout Tuesday, accounts for the majority of outages. Contra Costa County led the way with 43,812 outages, while San Mateo County was close behind with 42,087 outages. San Francisco County (34,899 outages) and Santa Clara County (22,049), home to San Jose, also accounted for a good chunk of the outages.
The latest storms moving throughout California continue to produce excessive rain and snow, along with gusty winds that have cut down trees in the Bay Area. In Tulare County, just outside of Fresno, downpours were so heavy in the afternoon that cars were sitting in flood waters along the Tule River.

Cars sit in flood waters by Central Valley farmland along the Tule River in Tulare County during a winter storm near Corcoran, California on March 21, 2023. (Photo by Patrick T. Fallon/AFP)
AccuWeather California Expert Ken Clark forecasts trouble in the evening hours farther south, with rainfall forecast to pick up in several Southern California metro areas. “This is going to make for a miserable evening commute for Ventura County into the [Los Angeles] area, and the Inland Empire down to San Diego,” Clark said. Clark also noted that snowfall will continue to impact already hard-hit areas, such as the San Bernardino County mountains.
Severe thunderstorms began barreling into California yet again on March 21, causing tens of thousands of power outages.
One person was killed in Stanford, California, Tuesday afternoon when a falling tree struck a car, according to law enforcement. Another person was killed when a tree fell onto their vehicle, around the same time, north of San Francisco near Temelec, California. In less than two hours Tuesday afternoon, almost 50 spotter reports of wind damage, mostly power lines and trees down in roadways, were submitted to the National Weather Service. Most of the reports were within 30 miles of Santa Cruz, California. During that time, a weather station north of Santa Clara at Mount Alison recorded a gust to 81 mph, while another station measured a 75 mph gust in the mountains to the south of San Jose near Lexington Hills.
Another round of significant precipitation is in store for California this week, a follow-up from a relatively weaker storm that took place this past weekend. After a brief reprieve from the stormy pattern, rainfall came back to the state between Saturday and Sunday, along with more heavy snow in the Sierra Nevada. However, the storm was not classified as an atmospheric river, like previous events. In the city of Santa Rosa, roughly 55 miles north of San Francisco, Sunday’s storm added to a staggering rainfall total. The city has officially received more than triple its historical average rainfall for the month of March, taking in 9.34 inches of rainfall as of Monday. By this point in the month, Santa Rosa typically receives just under 3 inches. Sunday’s storm also forced new evacuation orders near two central California towns, Alpaugh and Allensworth, due to “the possibility of residents becoming isolated due to impassable roadways.”
Cities in Southern California that have already seen double or nearly double the historic average of rainfall since November will see totals elevated with the new storm. Los Angeles is among such cities, having picked up 24.49 inches of rain at the downtown site as of March 18. That’s a staggering 208% of the area’s historical average rainfall of 11.78 inches to date. Farther west, Santa Barbara has received nearly double its typical total of 14.04 inches, tallying 24.14 inches of rain. The total includes one boost of 4.22 inches of rain that fell on Jan. 9 amid an atmospheric river event.
Travel impacts have begun to take place in California due to weather hazards, including in Los Angeles. In the city’s Elysian Park area, the right lane of the southbound Interstate 5 connector to State Route 110 was closed off Tuesday morning, local time, due to a mudslide and flooding. Farther south in San Diego, several Mission Valley area river-crossing roads will be closed at 9 p.m., local time, in anticipation of heavy rains. Meanwhile, snow-covered roads have made travel difficult in Northern California, with conditions quickly deteriorating Tuesday at Donner Pass. Snowfall has also impacted California’s neighbor to the southeast, with snow covering roads in the high country of Arizona. The Arizona Department of Transportation warned that motorists “should use extra caution, expect slick roads and pack an emergency travel kit.”

A radar loop of the area around Santa Cruz, California, on March 21, 2023. (AccuWeather)
The risks of power outages and trees being blown over are increasing near the coast of central California as strong winds pivot onshore. AccuWeather Storm Warning Meteorologist William Clark warned that “potentially damaging winds [are] approaching Santa Cruz,” with winds likely exceeding 60 mph. One of the low pressure centers of the storm resembled the eye of a hurricane on radar, although the structure of the storm system is significantly different than that of a hurricane. The storm center is likely to move over Santa Cruz early Tuesday afternoon.
Strong winds at San Francisco International Airport were to blame for the growing number of delays on Tuesday. Roughly 220 flights at the airport were delayed amid the storm as of noon, local time, according to FlightAware. Departures at the airport were delayed by 110 minutes on average due to the wind. A wind advisory was in effect for the area and is set to expire by 9 p.m., local time, Tuesday. A gust of 44 mph had already been recorded before noon. Delays were also rising in San Diego and Los Angeles in Southern California. At San Diego International Airport, 105 flights had been delayed, and another 190 had been delayed at Los Angeles International.
With another round of mountain snow hitting the Sierra Nevada this week, snowfall totals are approaching record territory in parts of the mountain range. According to the UC Berkeley Central Sierra Snow Lab, 677 inches of snow accumulated in the Central Sierra since Oct. 1, 2022, making the 2022-23 snow season the second-highest figure on record. With 7.7 inches of snow accounted for on Sunday, the Central Sierra snow total has surpassed the 1982-83 season, a prolific year for snow in the West. The 2022-23 totals only trail behind the 1951-52 season, when 812 inches of snow was recorded. Overall, the Central Sierra was at 229% of normal snowpack as of Monday, joining impressive snow totals in the Southern Sierra (278% of normal) and the Northern Sierra (181% of normal).
The National Weather Service issued a high wind warning for San Diego that will expire at midnight, local time. Winds have already gusted over 35 mph at the San Diego International Airport, with gusts of 55 mph expected. Gusts of this intensity can damage trees and power lines, potentially causing power outages. Motorists are cautioned to drive carefully at this time. A severe thunderstorm warning was issued for 2.3 million people in and around San Diego Tuesday morning as a line of intense, wind-driven rain approached the city. It was the first severe thunderstorm warning issued by the National Weather Service office in San Diego since Oct. 17, 2022.

A radar image from Tuesday morning that shows the center of the storm southwest of the Bay Area. (AccuWeather)
The powerful storm slamming California is far from a hurricane, but the center of the system could be seen on radar just off the coast southwest of the Bay Area.“The intensifying storm off the California coast almost [has] an ‘eye’ structure,” said AccuWeather Chief Meteorologist Jonathan Porter. “We see that on rapidly developing storms at times.” When the center of the storm passes by San Francisco, it could challenge the March low-pressure record for the city, which currently stands at 29.24 inches of mercury (990.2 millibars).

A satellite view of the California coast late Tuesday morning.
Atmospheric rivers are plumes of tropical moisture in the atmosphere that can deliver heavy rainfall or snowfall, but is that what’s driving the current storm in the West? While heavy rainfall will remain a threat, the heaviest concentration of moisture will focus on northern Mexico. The European Model forecast, as shown by the Center for Western Weather and Water Extremes at the Scripps Institution of Oceanography at UC San Diego, says that an atmospheric river is only forecast from around Oceanside, California, southward through San Diego and into the Baja California peninsula in Mexico.
“It seems the plume of moisture was penciling out upon reaching the coast of Central and Southern California early Tuesday morning but may tend to focus the fire-hose effect more on northwestern Mexico from here on out,” AccuWeather Senior Meteorologist Alex Sosnowski said. However, this won’t mean flooding rainfall, mudslides and major travel disruptions in the region are out of the question. “It will not take as much rain to cause problems as the ground is still wet from prior storms, and streams and rivers are already running high from the same,” Sosnowski said.

California’s largest reservoir continues to hold an impressive amount of water thanks to a bevy of atmospheric rivers hitting the state. As of Monday, Lake Oroville held 123% of water storage compared to the historical average for the date; this is one of several major reservoirs to be above average due to the rounds of storms. The California Department of Water Resources, working with dam operators, announced that the release flow of water from Oroville increased to 35,000 cubic feet of water per second this past week. March has been the first time the main spillway at Oroville opened since April 2019. The latest pair of atmospheric rivers in the state produced the highest inflows into Lake Oroville, with saturated soil and melting snow pointed to as important factors. The increase in the amount of water released forced road closures, including approximately 3 miles of roadway directly across from the main spillway at the Oroville dam. Other major reservoirs holding more than 100% of the historical average include Don Pedro, Millerton and Folsom.

Strong winds associated with the next round of California storms will likely come from an uncommon direction for the area, which could increase the risk of toppled trees and power outages. AccuWeather forecasters warn that winds from the approaching storm are likely to come from the south or southwest — a wind direction that the area doesn’t typically experience. Wind roses across the southern portion of the state showed that strong winds are much more common from the west, northwest or sometimes southeast.
“This is important because my experience is that when damaging winds originate from wind direction uncommon for them to do so, you increase the risk for lots of problems with trees toppling,” AccuWeather Chief Meteorologist Jonathan Porter said. “[This is] likely because the root systems of the trees ‘build up’ over time to be more supportive of force from the common wind directions and thereby less supportive of force from the uncommon wind directions.” He added that a similar situation occurred in 2020 when Tropical Storm Isaias tore through the Northeast, causing widespread and long-lasting power outages as winds had come from the southeast — an unusual winds direction for strong winds in the region.

It is a soggy start to the day across Southern California as rain and mountain snow spread across the state. Raincoats and umbrellas will come in handy throughout the morning commute, although gusty winds could make it a little challenging to hold on to an umbrella with winds already gusting near 30 mph in San Diego. Rain is also starting to fall elsewhere across the state, including San Francisco and Fresno. Rain showers will also be possible in Death Valley Tuesday as precipitation moves farther inland.
Although California residents have received a small break from severe weather, the state’s transportation staff remained hard at work, clearing out highways that have been overwhelmed with snow. Caltrans District 3, which maintains highways in 11 Northern California counties, shared images of workers carving out a portion of State Route 89 Sunday evening. Crews used heavy-duty equipment, such as a massive plow, to clear snow off the route around Emerald Bay, roughly 115 miles northeast of Sacramento. “Our crews are literally working around the clock to repair roadways in between storms,” Caltrans District 3 wrote on Twitter. “Please give them room to work, they want to make it home safe and sound too.” Another round of robust mountain snow will make its way through the Sierra Nevada beginning Tuesday, though the amount may not be as excessive as amounts from prior storms.
At over 11,000 feet of elevation, the highest summit of any California ski resort resides at Mammoth Mountain, which boasts 3,500 skiable acres for winter sports fanatics. Mammoth Mountain has been on a historical run of snowfall during the 2022-23 season, hitting 634 total inches as of Monday. The total snowfall puts this season as the second-snowiest on record, only trailing an accumulation of 668.5 inches during the 2010-11 season.
This is just the third time on record that Mammoth Mountain has measured over 600 inches of snow, dating back to the winter of 1969-70. “It’s incredible to see how buried the mountain is,” Mammoth Mountain Ski Area Communications Director Lauren Burke told AccuWeather. Burke also said several ski lifts were recently completely buried due to a “monumental amount of snow,” taking crews anywhere from four to six hours to clear snow from a single lift. This week's storm may boost this season's snowfall into the top spot, with Burke saying she thinks "this is the year to break the all-time record."

David Frazier, 69, walks across Davison Road after a day of skiing March 7, 2023 in Mammoth Mountain, California. (Wally Skalij/Los Angeles Times via Getty Images)
With another powerful storm hitting California this week, AccuWeather meteorologists say that precipitation will not be the only hazard to watch out for. On Tuesday, strong onshore winds will accompany rainfall and snow, with gusts of up to 75 mph possible along the coastline from the San Francisco Bay Area to near the U.S./Mexico border. Even stronger winds are in store for mountainous regions, with AccuWeather Local StormMax™ gusts forecast to be near 100 mph over mountain passes and ridges.
“Winds are likely to be strong enough to knock over many trees, which can not only block roads but also trigger widespread power outages,” AccuWeather Senior Meteorologist Alex Sosnowski said. “The saturated soil will play a major role in the number of downed trees.” A mass amount of power outages impacted the Bay Area last week due to the high winds, including gusts that reached 97 mph in Loma Prieta, roughly 20 miles south of San Jose.
