A series of late winter storms has been hitting Southern California since Tuesday, March 11, bringing showers on Tuesday with stronger rainfall expected on Wednesday and Thursday, continuing through Friday.
According to the city news agency, the Los Angeles Fire Department announced on Tuesday that a significant amount of rainfall is expected in Los Angeles County on Wednesday and Thursday. Authorities have issued evacuation orders for potential mudslide-prone areas, including recent wildfire burn areas, starting from 7 a.m. on Wednesday until 6 p.m. on Thursday.
Fire officials stated that areas affected by the Palisades Fire, Sunset Fire, and Hurst Fire are particularly susceptible to the impact of heavy rainfall. The Los Angeles Police Department began inspecting homes at higher risk within warning areas on Tuesday and providing specific evacuation orders. Flyers with relevant information will be left at residences if residents are not present.
The storm is anticipated to cause traffic safety issues, prompting the California Department of Transportation (Caltrans) to close sections of the Pacific Coast Highway (PCH) in burn areas on Wednesday noon, allowing passage only to emergency vehicles and contractors for debris removal by the US Army Corps of Engineers. Residents in burn areas are advised to consider alternative routes in the afternoon or opt for remote work.
Caltrans and other officials are scheduled to reassess the situation on Thursday to determine if the PCH highway can be reopened before the Friday morning commute peak or even earlier. The final decision will be based on the storm’s intensity and the extent of mudslide impact.
Authorities have reported that the Los Angeles County Public Works Department has cleared debris basins, stabilized slopes, and reinforced draining systems to reduce flood risks, particularly in recent burn areas such as the Eaton Fire, Palisades Fire, and Bridge Fire. However, the department cautioned that despite these measures reducing flood risks, the storm may still result in moderate mudslides, potentially blocking roads and posing threats to structures, depending on the location and terrain. The department also mentioned that to minimize potential impacts, continuous 24-hour surveillance has been initiated by the Los Angeles County Public Works Department.
As per the National Weather Service forecast, as of Tuesday night, rainfall amounts ranged from 1/3 inch to 2/3 inch from the coast to mountain regions, with localized areas possibly exceeding 1 inch in mountainous regions. A cold front is expected to pass through the Los Angeles area from late Wednesday to early Thursday, bringing widespread heavy rainfall that could lead to flooding.
Expected rainfall amounts in coastal and valley areas range from 1 to 2 inches, increasing to 2 to 4 inches in foothills and mountain regions, with rainfall intensity possibly reaching 0.75 inches per hour. Additionally, this storm is forecasted to bring the largest snow accumulation of the season, with higher elevations expected to receive 1 to 2 feet of snow.
The weather service mentioned that on Thursday, ongoing rainfall will transition into showers, and the snow level is predicted to drop to around 3,000 feet, with the Grapevine region and other lower elevation mountain passes potentially receiving several inches of snow.
Strong southwest to west winds are expected from Wednesday night to Thursday night.
The Los Angeles area is forecasted to experience a drop in temperatures this week, with daytime highs in downtown Los Angeles reaching around 60 degrees Fahrenheit on Tuesday and Wednesday, decreasing to about 55 degrees Fahrenheit on Thursday and Friday. Nighttime lows are expected to range from 40-50 degrees Fahrenheit, while mountainous areas, Santa Clarita, and Antelope Valley regions will see lows around 30 degrees Fahrenheit on Thursday and Friday.
Meteorologists indicated that on Friday, a weaker storm system will move into the northern inland regions, potentially bringing some precipitation on Friday night. However, dry and warmer weather is expected over the weekend.