Southern California’s rainy winter continued this weekend, though the intensity of the rainfall was expected to taper off.
The latest forecast showed a weakening of the system as it moves into Los Angeles County, but there is a 20% chance that recent burn areas such as the Palisades, Eaton, and Bridge burn scars could see rainfall rates capable of producing debris flows, the National Weather Service said Saturday.
“A Flash Flood Watch may still be issued later today if the environment starts to show favorable signals for heavy rainfall,” the NWS said. “Storm total rainfall is expected to reach between one and three inches for the coastal and valley regions, while the foothills and mountains could see significantly higher totals ranging from three to six inches. Snow levels are projected to remain relatively high throughout the event, staying mostly above 6,500 feet.”
Temperatures were expected to stay in the 50s and 60s, with overnight lows dropping into the 30s and 40 throughout the Southland.
The latest in a series of winter storms prompted evacuation warnings near the burn scars of recent wildfires and another closure of a 3.6-mile stretch of Topanga Canyon.
On Friday, the city of Los Angeles issued an evacuation warning, starting at 10 a.m. for the Sunset Fire area, as well as for the Hurst Fire and Mandeville areas regarding “possible post-fire debris flows.” According to the Los Angeles Fire Department, “Houses in the warning area with high risk will be visited by LAPD with protective information.”
An evacuation warning was also issued for part of the Hollywood Hills starting at 10 a.m. Saturday. The LAFD was providing free, ready-to-fill sandbags at neighborhood fire stations.
In another preemptive move in anticipation of possible mud and debris flows, Caltrans closed the 3.6-mile stretch of Topanga Canyon Boulevard known to experience mudslides between Pacific Coast Highway and Grand View Drive, in the unincorporated Topanga area. The closure began midnight Friday into Saturday. The reopening of the roadway was “dependent on improved weather and road conditions,” Caltrans said.
The agency also said the Palisades Fire recovery work zone on PCH from Sunset Boulevard to Carbon Beach Terrace will remain open, “with crews on standby to respond to any storm impacts.”
According to Caltrans, the New Year’s Eve storms “brought very minor impacts to PCH.”
Meanwhile, state Route 2 was closed from 3.3 miles east of Newcomb’s Ranch in La Canada Flintridge to state Route 138 in the Angeles National Forest.
In addition, the L.A. County Department of Public Health issued a rain advisory Friday, warning beach users “to avoid all water contact, especially near discharging storm drains, creeks, and rivers due to potentially higher bacteria levels in these areas. This includes any runoff that may flow onto or pond on the beach sand.” The advisory will be in effect until at least Monday at 4 p.m.
Inner Cabrillo Beach in San Pedro also remains closed from a Christmas Day sewage flow, and will remain closed until further notice, the health department said. Hilda Solis, chair of the L.A. County Board of Supervisors, said county departments were “actively monitoring conditions and stand ready to respond to emergencies as needed.”
For up-to-date information on the storm, residents can visit lacounty.gov/emergency or sign up for emergency alerts at alert.lacounty.gov. Sand and sandbag distribution sites can be found at pw.lacounty.gov/dsg/sandbags. To check on evacuation statuses, residents can download the Genasys Alert app or visit genasys.com. Motorists were also advised to stay off the roads if possible and to exercise extreme caution if they do drive.
Forecasters said the initial estimate is a quarter- to half-inch per hour with isolated rates up to .75 of an inch during the most intense storm period Saturday. Thunderstorm potential looked minimal, but a beach hazards statement was also issued for Orange County, where tides could combine with southerly winds at times to bring minor tidal overflows at area beaches.
The weather service added that several significant storms affecting southwestern California from October through December have brought seasonal rainfall totals already close to or above normal full-season levels, with January and February still to come. Although active rainfall was mostly on pause during Thursday’s 137th Tournament of Roses Parade, the route along Colorado Boulevard was rain-slickened for the first time in 20 years, skies were uncharacteristically overcast, and many in the crowd wore ponchos to protect themselves from the overnight rain.
State and local officials also have precautions in place for weather-related emergency response needs. Gov. Gavin Newsom has directed the California Governor’s Office of Emergency Services to pre-position fire and rescue personnel and resources in areas most at risk for flooding, mud, and debris flows — including parts of Southern California, with a particular eye toward burn scar areas. Los Angeles Mayor Karen Bass’ office said the city’s Emergency Operations Center was activated Wednesday to coordinate preparedness measures and ensure all personnel are ready to respond as needed. Bass added that the LAFD had augmented staffing of specialized resources that can assist with swift water rescues, mud and debris flows, and other rain-related issues with a specific focus in burn scar areas.
Additionally, the Los Angeles Department of Water and Power was poised to respond to any potential power outages and will work around the clock to meet customer demand, according to the mayor’s office. L.A. Sanitation was also on standby to assist with any flooding calls and with monitoring the city’s wastewater conveyance system to manage the additional incoming water flow. The L.A. County Board of Supervisors held a special meeting Wednesday, when the board ratified a local emergency proclamation issued earlier by Solis.
The proclamation allows the county “to seek reimbursement for storm-related damages and accelerate recovery efforts” and ensure that “resources and assistance can be deployed quickly to support residents and communities affected by the storms.”
Forecasters cited a 30%-40% chance of more showers on Monday and Tuesday, with skies likely clearing up after that.