The heaviest rain arrives Thursday morning. Belen De Leon has the forecast for Thursday Jan. 5, 2022.
What to Know
Downpours left some streets flooded early Thursday ahead of the morning drive.
Rain increased late Wednesday and continued to soak Southern California overnight.
Gov. Gavin Newsom proclaimed a state of emergency throughout California due to severe weather.
A powerful winter storm that brought heavy rain overnight continued to pound Southern California with heavy downpours that flooded streets and threatened to trigger debris flows in the region's wildfire burn areas.
"This morning is when we're going to see the heaviest rain," said NBC4 forecaster Belen De Leon. "It's very unsettled weather as we go throughout the day."
The Sepulveda Basin from Burbank Boulevard to the 405 Freeway and Balboa Boulevard and Woodley Avenue from Burbank and Victory boulevards were closed due to flooding. Flooded roads also were reported in the Sun Valley area.
In Mailbu, State Route 23 was closed in both directions from Pacific Coast Highway to Decker School Road due to a rockslide.
Evacuations were ordered for those living in areas burned by three recent wildfires in Santa Barbara County. Among the towns ordered to evacuate was Montecito, where five years ago huge boulders, mud and debris swept down mountains through the town to the shoreline, killing 23 people and destroying more than 100 homes.
Underscoring the severity of the West Coast storm, Gov. Gavin Newsom proclaimed a state of emergency throughout California. The declaration bolsters emergency response efforts and authorizes the mobilization of the California National Guard for disaster response.
Here's what to know about the storm, weather alerts, travel conditions and more.
Here we go! First Alert Radar is showing heavy rain falling in LA County and moving east. The morning will be the rainiest period, then expect scattered activity during the afternoon with a chance for t-storms. What's the weather like for you? #LARain@NBCLApic.twitter.com/o6BiV5HEXz
Rainfall will range from one-tenth to a quarter-inch per hour in some areas early Wednesday. The rain will increase steadily, with downpours continuing into Thursday and reaching an inch per hour in some locations.
The storm's peak intensity is expected to deliver the heaviest rain Thursday morning. Two to 4 inches of rain could fall across most of the area, with some mountain areas receiving 4 to 8 inches.
With SoCal's storm weather, you might be wondering what these terms mean. Shanna Mendiola explains Wednesday, Jan. 4, 2023.
Los Angeles and Ventura counties can expect the most rainfall. Los Angeles County is forecasted to get 1-3 inches, with most of the rain falling between 12 a.m. and 9 a.m. Thursday, NBCLA meteorologist David Biggar forecasted. Ventura County could get an inch-and-a-half to four inches, especially in the higher elevations.
Downpours could result in flash flooding and debris flows.
In the San Gabriel Valley, K-rails were installed on streets in a foothill neighborhood in Duarte, where the storm raises the risk of destructive mud and debris flows.
The front has passed thru the area- the threat of flash flooding still exists for Ventura/LA Co. Showers will continue off & on w/ heavier showers possible. Isolated thunderstorms are possible this afternoon due to the unstable airmass over the area.#LArain#CAwxpic.twitter.com/VpQ3I9qkCP
A flood watch will be in effect Wednesday evening through Thursday afternoon for most of the region. That's just one of the weather alerts to know about.
In Topanga Canyon, State Route 27 (Topanga Canyon Blvd.) is closed in both directions from State Route 1 (PCH) to Grand View Dr. due to a mud slide. It is expected to be closed until Friday morning, Jan. 6, Caltrans says.
In Santa Barbara County, an evacuation order was issued for people residing in the area of the Alisal, Thomas and Cave Fire burn scars.
In Orange County, the flood watch will be in effect Thursday morning through Thursday afternoon.
A high surf advisory was in effect from 6 a.m. Thursday to 10 a.m. Friday.
A winter storm warning will be in effect from 6 p.m. Wednesday to 10 p.m. Thursday for the Los Angeles County Mountains including the cities of Acton and Mount Wilson.
A wind advisory will be in effect in Orange County from 2 a.m. to 4 p.m. Thursday, with winds of 15 to 25 mph possible, including gusts of up to 40 mph
Wind watches could be issued in Los Angeles County mountains and deserts.
A wind advisory was in place for San Bernardino and Riverside county valleys.
A surfer gets a tube ride while riding a big wave generated by recent storms at the Seal Beach pier Wednesday, Jan. 11, 2023. (Allen J. Schaben / Los Angeles Times via Getty Images)
A boogie boarder heading out to ride big waves walks past rash and debris covering a portion of the beach after recent storms brought debris-flows and flooding across parts of Seal Beach near the San Gabriel River Wednesday, Jan. 11, 2023 in Seal Beach, CA. (Allen J. Schaben / Los Angeles Times via Getty Images)
Damaged cars sit beneath a fallen tree at the El Camino Shopping Center on Mulholland Drive in Woodland Hills on Sunday, Jan. 15, 2023. The tree fell Saturday night trapping some people inside the cars. (Myung J. Chun / Los Angeles Times via Getty Images)
Damaged cars sit beneath a fallen tree at the El Camino Shopping Center on Mulholland Drive in Woodland Hills on Sunday, Jan. 15, 2023. The tree fell Saturday night trapping some people inside the cars. (Myung J. Chun / Los Angeles Times via Getty Images)
Getty
In an aerial view, workers inspect a railway bridge over Hopper Creek that is covered in storm debris on January 11, 2023 near Fillmore, California. (Photo by David McNew/Getty Images)
A resident keeps watch on Fredonia Drive in Studio City where a mudslide is blocking the road during the storm on Tuesday, January 10, 2023. Credit: Getty
Flooding at the western-style Alisal Ranch & Resort as seen on January 9, 2023, in Solvang, California. Credit: Getty
NBCLA
A downed tree pictured during a Jan. 10, 2023 SoCal storm.
A mudslide flooded parts of Fredonia Drive in Studio City during a storm on Tuesday, January 10, 2023. (Photo by Sarah Reingewirtz, Los Angeles Daily News/SCNG)
Flooding at the popular western-style Alisal Ranch & Resort, a favorite hideaway of Hollywood celebrities, as viewed on January 9, 2023, in Solvang, California. Credit: Getty
Getty
A resident attempts to help a vehicle stuck on Fredonia Drive in Studio City where a mudslide is blocking the road during the storm on Tuesday, January 10, 2023. (Photo by Sarah Reingewirtz, Los Angeles Daily News/SCNG)
John Cádiz Klemack
Two vehicles fell into a sinkhole Monday Jan. 9, 2023 in Chatsworth.
Tracey Leong/NBCLA
A storm leaves cars partially submerged in Studio City Tuesday Jan. 10, 2023.
MONTECITO, CA-JANUARY 9, 2023:Jameson Lane in Montecito is flooded out, a result of San Ysidro creek overflowing due to heavy rainfall in the area. At left is the 101 freeway that was closed to all vehicles heading north. (Mel Melcon / Los Angeles Times via Getty Images)
MONTECITO, CA-JANUARY 9, 2023: Lifelong Montecito resident George Quirin, 63, photographs a flooded Jameson Lane in Monticito, a result of San Ysidro creek overflowing due to heay rainfall in the area. At left is the 101 freeway that was closed to all vehicles heading north. (Mel Melcon / Los Angeles Times via Getty Images)
LOS ANGELES, CALIFORNIA – JANUARY 09: Rain falls as the Los Angeles River flows at a strong rate on January 09, 2023 in Los Angeles, California. California continues to get drenched by powerful atmospheric river events that have brought high winds and flooding rains which have toppled trees, flooded roads and cut power to tens of thousands of residents. Storms are lined up over the Pacific Ocean and are expected to bring more rain and wind through the end of the week. (Photo by Mario Tama/Getty Images)
REDONDO BEACH-CA-JANUARY 9, 2023: Surfers walk The Esplanade after riding the waves in Redondo Beach on Monday, January 9, 2023. (Christina House / Los Angeles Times via Getty Images)
Getty
Beverly Hills, CA – January 09: Amidst rain showers, crew members take photos as they are reflected in pools of water while setting up the red carpet for the 80th Golden Globe Awards at The Beverly Hilton in Beverly Hills Monday, Jan. 9, 2023. (Allen J. Schaben / Los Angeles Times via Getty Images)
LOS ANGELES, CA-JANUARY 9, 2023: Brayan Suarez leaps to avoid getting wet while crossing to the other side as the rain water builds up on the ground at Santee Alley in Los Angeles. (Mel Melcon / Los Angeles Times via Getty Images)
Getty
Jason Darby, a supervisor with the Los Angeles Dept. of Water and Power, gets a closer look at a landslide on Mullholland Drive near Summit Circle in Beverly Hills, caused by the recent rains. (Mel Melcon / Los Angeles Times via Getty Images)
Getty
A person walks in the rain on a bridge crossing the Los Angeles River on January 09, 2023 in Los Angeles, CaliforniaGetty.
Atwater, CA – January 05: A man takes a closer look at rain-swollen LA River raging under Glendale Blvd. on Thursday, Jan. 5, 2023 in Atwater, CA. (Irfan Khan / Los Angeles Times via Getty Images)
Getty
Redondo Beach, CA – January 05: A young man runs from the spray of waves hitting and going over the breakwall of Redondo Beach, CA, Harbor, in the wake of a storm that cleared the south bay community of Los Angeles County, Thursday, Jan. 5, 2023. (Jay L. Clendenin / Los Angeles Times via Getty Images)
Sean Browning / NBCLA
A rainbow appears over a freeway in Canyon County on Thursday, Jan. 5, 2023.
Getty
People brave the elements along the Hermosa Beach Pier in Hermosa Beach, CA, as rain fell across Los Angeles County, Tuesday, Jan. 3, 2023. (Jay L. Clendenin / Los Angeles Times via Getty Images)
Getty
Seal Beach, CA – January 03: Beachgoers watch surfers south of the Seal Beach Pier during the rain in Seal Beach, CA, on Tuesday, January 3, 2023. (Photo by Jeff Gritchen/MediaNews Group/Orange County Register via Getty Images)
Getty
Seal Beach, CA – January 03: A visitors to Eisenhower Park hangs out near the Seal Beach, CA, on Tuesday, January 3, 2023. (Photo by Jeff Gritchen/MediaNews Group/Orange County Register via Getty Images)
Getty
Dave Smith, a professional dog walker, takes his seven dogs out for their late-morning stroll along the Esplanade in Redondo Beach, CA, as rain fell across Los Angeles County, Tuesday, Jan. 3, 2023. (Jay L. Clendenin / Los Angeles Times via Getty Images)
Getty
Mannequins are covered in plastic along W 8th St. in central Los Angeles as a light mist of rain falls on Jan. 3, 2023. Rain is expected for the the first week of January, with light mist filing in Los Angeles on Jan. 3, 2022. (Carolyn Cole / Los Angeles Times via Getty Images)
Juan Marcos/UGC
Juan Marcos shared this image in which a flood is seen in Sherman Oaks, California.
Suzanne Detwiler/UGC
Suzanne Detwiler shared a picture from Lake Arrowhead: “About 2 inches of snow at 5500 feet”, she wrote.
Getty
LOS ANGELES, CALIF. – JAN. 4, 2023. Rain clouds shroud the skyline of downtown Los Angeles on a rainy Wednesday afternoon, Jan. 4, 2023. Another storm is expected to bring heavier rain overnight. (Luis Sinco / Los Angeles Times via Getty Images)
Getty
Duarte, CA – January 04: Another storm is moving into Southern California, bringing heavy rain to the area today and Thursday. Heeding forecasters warning of K-rails are placed to protect homes from possible flooding and mudflows from mountain along 200 block of Melcanyon Road on Wednesday, Jan. 4, 2023 in Duarte, CA. (Irfan Khan / Los Angeles Times via Getty Images)
Los Angeles, CA – January 04: Vehicles make their way through the rain filled intersection of Glenoaks Boulevard and Tuxford Street in Sun Valley Wed, Jan 4, 2023. (Photo by Hans Gutknecht/MediaNews Group/Los Angeles Daily News via Getty Images)
LOS ANGELES, CALIF. – JAN. 4, 2023. Rain slicks Grand Avenue in downtown Los Angeles on a wet Wednesday afternoon, Jan. 4, 2023. Another storm is expected to bring heavier rain overnight. (Luis Sinco / Los Angeles Times via Getty Images)
LOS ANGELES, CALIF. – JAN. 4, 2023. The Arzate family, visiting from Phoenix, wait to cross Hill Street in downtown Los Angeles on a rainy Wednesday afternoon, Jan. 4, 2023. Another storm is expected to bring heavier rain overnight. (Luis Sinco / Los Angeles Times via Getty Images)
LOS ANGELES, CALIF. – JAN. 4, 2023. Rabbi Yuval Noff walks in the rain on Hill Street on a wet Wednesday afternoon, Jan. 4, 2023, in Los Angeles. Another storm is expected to bring heavier rain through the night](Luis Sinco / Los Angeles Times via Getty Images)
Los Angeles, CaliforniaJan. 4, 2023Mathew Prado, who works at the Sheraton Hotel at Universal Studio, sweeps water from the front drive. Heavy rain is falling in Los Angeles as another winter storm moves in. (Carolyn Cole / Los Angeles Times via Getty Images)
LOS ANGELES, CALIF. – JAN. 4, 2023. Rush hour traffic stacks up on the Harbor Freeway in downtown Los Angeles on a rainy Wednesday afternoon, Jan. 4, 2023. Another storm is expected to bring heavier rain overnight. (Luis Sinco / Los Angeles Times via Getty Images)
Getty
Southern California residents enjoy a late day hike on the snow-covered Big Falls Trailhead as dark storm clouds move in ahead of a major storm beginning Wednesday evening into Thursday on January 4, 2022 in Forest Falls California.(Gina Ferazzi / Los Angeles Times via Getty Images)
Caltrans
A rockslide closed part of Route 23 in Malibu Jan. 5, 2023.
Getty
Encino, CA – January 05: Migrating white pelicans huddle by rain-swollen Los Angeles River in Sepulveda Basin on Thursday, Jan. 5, 2023 in Encino, CA. (Irfan Khan / Los Angeles Times via Getty Images)
Encino, CA – January 05: Migrating white pelicans huddle by rain-swollen Los Angeles River in Sepulveda Basin on Thursday, Jan. 5, 2023 in Encino, CA. (Irfan Khan / Los Angeles Times via Getty Images)
NOVATO, CALIFORNIA – JANUARY 4, 2023: Warning messages for drivers are posted along US Highway 101 in Marin County before a powerful storm arrives to the area in Novato, California on Wednesday January 4, 2023.(Melina Mara/The Washington Post via Getty Images)
The beach during a rain storm in Hermosa Beach, California, US, on Thursday, Jan. 5, 2023. A powerful storm with hurricane-force gusts has begun to wind down after ripping across California, leaving behind power outages, flood threats and road closures just hours before another drenching is set to wash over the state. Photographer: Eric Thayer/Bloomberg via Getty Images
Traffic on a freeway during a rain storm in Los Angeles, California, US, on Thursday, Jan. 5, 2023. A powerful storm with hurricane-force gusts has begun to wind down after ripping across California, leaving behind power outages, flood threats and road closures just hours before another drenching is set to wash over the state. Photographer: Eric Thayer/Bloomberg via Getty Images
LOS ANGELES, CA – JANUARY 05: Motorists on the State Route 2 (SR 2) freeway are warned of severe weather and to avoid travel as a powerful storm slams into the West Coast on January 5, 2023 in Los Angeles, California. California is being inundated by a “Pineapple Express” storm, or atmospheric river, and a bomb cyclone, a rapidly rotating storm system, bringing heavy rain and wind, and the threat of widespread flooding and possible landslides near wildfire burn areas. Coastal areas may sustain damage and heavy snow is accumulating the mountains. The dangerous storm condition has prompted California Gov. Gavin Newsom to declare a state of emergency. (Photo by David McNew/Getty Images)
LOS ANGELES, CA – JANUARY 05: A motorist drives a flooded roadway as a powerful storm slams into the West Coast on January 5, 2023 in Los Angeles, California. California is being inundated by a “Pineapple Express” storm, or atmospheric river, and a bomb cyclone, a rapidly rotating storm system, bringing heavy rain and wind, and the threat of widespread flooding and possible landslides near wildfire burn areas. Coastal areas may sustain damage and heavy snow is accumulating the mountains. The dangerous storm condition has prompted California Gov. Gavin Newsom to declare a state of emergency. (Photo by David McNew/Getty Images)
Travel Warning Ahead of California Storm
Caltrans warned drivers statewide to stay off the roads if possible during the storm.
"Caltrans districts statewide are coordinating with local & state officials to assist with this latest storm system. TRAVEL IS NOT RECOMMENDED," the agency tweeted Tuesday.
Heavy snow was expected above 6,000 feet initially, but levels will drop Thursday, potentially affecting some of the higher roadways in the mountains, such as Angeles Crest and Big Pines highways in Los Angeles County.
The storm threat also led to a planned closure of Laurel Canyon Boulevard. The Los Angeles Department of Transportation announced that the canyon road will be closed between Hollywood Boulevard and Mulholland Drive from 8 a.m. to noon Wednesday.
"There will be many potential problems associated with this storm system including urban and small stream flooding, rocks and debris on roads, downed trees and numerous power outages, and mud and debris flows out of recent burn areas," the National Weather Service said.
Rainfall will decrease by Thursday night and into Friday.
More rain is possible over the weekend, but nothing to match the severity of Thursday's conditions. More rain was in the forecast early next week, with a chance of showers Sunday through Tuesday.
Temperatures will remain about six degrees cooler than normal through the weekend.
Northern California Flooding
But back-to-back-to-back powerful storms have left many Californians preparing for the worst.
On New Year's Eve, much of the state was drenched in heavy rain causing floods that killed one person and damaged a levee system in Sacramento County.
In San Francisco, crews were rushing to clear trash, leaves and silt that clogged some of the city's 25,000 storm drains during Saturday's downpour before the next storm hits later this week.
The National Weather Service is predicting up to 6 inches of rain in San Francisco with winds of speeds up to 30 mph with gusts of 60 mph.
Mayor London Breed said city workers may not have enough time to clean all the storm drains before Wednesday and asked the public to prepare by getting sandbags to prevent flooding, avoiding unnecessary travel and only calling 911 in a life-or-death emergency.
City officials had distributed 8,500 sandbags as of Tuesday, asking residents to only get them if they have experienced flooding in the past. Tink Troy, who lives in South San Francisco, picked up some sandbags from the city's public works department on Tuesday.
California Drought Update
Nearly 98 percent of the state remained in drought at the end of December. More than 80 percent of the state was in severe drought, the third most severe category in the weekly Drought Monitor report.
A swath of the agricultural Central Valley north of Los Angeles remained in exceptional drought, the most severe category. Extreme drought stretched from northern Los Angeles County through the central part of the state to the Oregon border.
California has spent most of the last 15 years in drought conditions. The current three-year dry spell included one of the driest late winters on record.
The state's normal wet season runs from late fall to the end of winter, but dismal precipitation left about 95 percent of California in severe drought at the start of spring. By September, nearly all of California was in drought.
Much of California’s water comes from melting snow in the Sierra Nevada Mountains. In an ideal scenario, storms blanket the mountains with snow during winter, building up the natural reservoir. That snow then melts in late spring and early summer, replenishing the state's water system. Snowpack was far below normal in Spring 2022.
Late fall storms brought reason for optimism. California's statewide snowpack level was more than 200 percent above normal in mid-December after powerful December storms blanketed the Sierra Nevada Mountains with snow.
In December 2021, statewide snowpack was at a dismal 22 percent to normal.
The Jan. 3 snowpack survey brought even more promising signs.
Scattered showers moved into Southern California early Wednesday as the region prepares for a powerful winter storm. Stephanie Olmo has the forecast for Wednesday Jan. 4, 2023.
