LOS ANGELES, California – A potentially catastrophic atmospheric river event is expected to strike California this weekend, posing a significant threat of flash flooding, mudslides, damaging winds, and heavy mountain snow. Nearly 40 million people, including those in San Francisco, Sacramento, Los Angeles, and San Diego, are under flood watches as the storm approaches.
The Los Angeles office of the National Weather Service issued a warning, stating that a prolonged period of heavy rain is likely to develop late Saturday night and continue through most of Sunday and Monday. This unprecedented storm could result in record-breaking amounts of rainfall across a wide area.
The Weather Prediction Center has issued a rare Level 4 risk of excessive rainfall for Santa Barbara and Oxnard on Sunday, while a more widespread Level 3 risk exists for much of coastal California. Such a high risk is issued on fewer than 4% of days per year on average, making this storm particularly noteworthy.
The prediction center cautions that at least 8 inches of rain is possible in less than 24 hours for portions of the Transverse Ranges in Southern California, with maximum totals just over 10 inches possible in certain locations. This level of rainfall is significant, especially considering that Los Angeles typically averages 2.99 inches of rain in February, its wettest month of the year on average.
As the storm approaches, the Ventura County Sheriff’s Office has issued evacuation orders for some communities, as well as warnings and advisories about the anticipated weather. The orders will be in place from 5 p.m. local time Saturday until 5 p.m. Sunday, in anticipation of the impacts related to the forecasted rain this weekend. The office also warned residents of the potential for landslides or debris flows due to the expected heavy rainfall.
In light of the potential impacts of the storm, Los Angeles Mayor Karen Bass has advised residents to take necessary precautions, emphasizing the need to stay at home, off the roads, and to stay informed about the latest information. Given the heightened concerns for flooding and mudslides, it is vital for the public to be prepared with emergency supplies.
This new atmospheric river comes on the heels of a previous storm that brought record rainfall to California, but this upcoming storm is expected to be much slower, lingering onshore for an extended duration and resulting in more prolonged periods of rain. Flooding and mudslide concerns are heightened due to the already saturated ground from the previous storm, and high winds are also expected to cause widespread damage across much of California.
Beyond rain and wind, the storm is also anticipated to bring significant snowfall. The National Weather Service office in Reno, Nevada, has warned of major travel impacts in the Sierra from Sunday through Tuesday due to heavy snowfall, advising people to prepare and hunker down until the storm subsides. In eastern California, Mono County is expected to experience notably higher snowfall totals as a result of the storm.
With the impending threat of severe weather, officials and residents across California are bracing for the potentially devastating impacts of this powerful atmospheric river. As the state prepares for this historic storm, it is crucial for people to heed official warnings and take necessary precautions to ensure their safety.