California Faces Flood and Mudslide Threat from Severe Atmospheric River |
An intense, prolonged atmospheric river is advancing into California this Sunday, carrying the potential for "life-threatening" flooding, mudslides, and widespread power outages due to substantial rainfall and snowfall.
Here are the latest developments:
- Unprecedented flood risk:
A rare Level 4 out of 4 risk of excessive rainfall now includes Los Angeles, Santa Barbara, and Oxnard in Southern California. The Weather Prediction Center warns of "life-threatening flash and urban flash flooding." Rainfall rates up to an inch per hour may bring 3 to 6 inches of rain to the area. A Level 3 risk is widespread for much of coastal California, including San Francisco.
- Significant rainfall in Los Angeles:
Central and Southern California anticipate widespread rainfall of 3 to 6 inches – surpassing a typical month's worth of rain. Los Angeles Mayor Karen Bass noted similarities to Tropical Storm Hilary from last August, emphasizing the need for residents to take "common sense precautions" during a news conference on Friday.
Mandatory evacuation orders have been issued for communities in Santa Barbara, San José, Los Angeles, and Ventura County as officials caution residents about the potential for "life-threatening" floods and landslides from the ongoing atmospheric event. In an unprecedented move, the National Weather Service in San Francisco has issued its first-ever hurricane force wind warning. Wind advisories and high wind warnings affect nearly 30 million people across inland areas from Redding to San Diego.
The storm is expected to bring substantial snowfall in eastern California and along the Nevada border. The Sierra Nevada will experience heavy wet snow with accumulation rates of 2 to 3 inches per hour, leading to "near impossible" travel conditions above 5000-6000 feet, according to the weather service.
Additionally, widespread power outages are anticipated due to powerful winds, ranging from 40 to 60 mph across much of California, with some gusts reaching as high as 95 mph in the foothills and mountains. Forecasters are advising residents to prepare for downed trees and potential power disruptions on Sunday and Monday.
California prepares for an imminent threat of flooded roadways and swollen rivers as an atmospheric river, characterized by a long, narrow moisture band, is set to unleash prolonged rainfall. Following a recent storm that brought record rainfall to the state, this slower-moving system is expected to stall upon reaching the shore, resulting in an extended period of rain compared to its predecessor.
The most severe impacts are projected between Sunday and Tuesday, particularly along the central and southern coastline, affecting areas like Los Angeles and San Diego. Eric Schoening from the National Weather Service emphasizes the potential for life and property-threatening flooding, urging caution on flooded roadways.
Anticipating widespread issues, officials warn of potential floods, mudslides, and debris flows, with predictions of over 8 inches of rain in under 24 hours in certain areas of Southern California. Over 8,500 personnel, including swift water and helicopter rescue teams, are on standby statewide to address potential emergencies, according to Nancy Ward, director of the California Governor’s Office of Emergency Services.
Highlighting the gravity of the situation, Ward emphasizes the forthcoming storms as significant and dangerous, surpassing the risk posed by wildfires. The state has prepared over 7 million sandbags, and rescue equipment is on standby. Californians are advised to brace for potential power outages as part of the storm's impact.
Potent onshore winds will exert their impact across northern and central California until Sunday, subsequently shifting to southern California by Sunday night, as reported by the National Weather Service.
Comprehensive wind advisories and high wind warnings cover virtually the entire state, affecting nearly 30 million residents from Redding down to San Diego. Officials strongly advise Californians to prepare alternative power sources in the event of power outages and to refrain from non-essential travel during the storm's peak.
Describing the storm as "very, very dangerous," Nancy Ward emphasizes the importance of self-care, looking out for loved ones, and checking on vulnerable neighbors, particularly those who may be homebound.