Feb. 4 (UPI) — California residents are bracing for “life-threatening” flooding, mudslides and power outages as an atmospheric river moves in Sunday, which is forecast to cause record rainfall and emergency conditions through Tuesday.
Thirty-seven million people are at risk for record flooding, according to forecasters.
The powerful storm is projected to dump a month’s worth of rainfall on Los Angeles in the span of four hours and cause heavy snowfall on other parts of the state, as well.
An atmospheric river is a long, narrow moisture band that carries saturated air thousands of miles then discharges it like a fire hose, weather experts explain.
Rainfall rates of up to an inch per hour will bring 3 to 6 inches of rain in Los Angeles, in addition to Santa Barbara and Oxnard.
A more widespread risk exists for much of coastal California, including San Francisco, potentially causing “life threatening flash and urban flash flooding,” CNN’s weather prediction said.
Forecasters expanded the excessive rainfall alert to a maximum Level 4 on Sunday, which pulled Los Angeles and other locales in southern California into the warning.
The storm has the potential to be as strong as Tropical Storm Hilary, which hit last August.
During a news conference Friday, Los Angeles Mayor Karen Bass encouraged residents to take “common sense precautions.”
Residents of Santa Barbara, San José, Los Angeles and Ventura County have been issued mandatory evacuation orders, warning residents of potential “life-threatening” floods and landslides from the potent atmospheric event.
In-person classes in Santa Barbara County and at other school districts have been canceled on Monday due to the treacherous weather.
For the first time since records have been kept, the National Weather Service in San Francisco on Sunday issued a hurricane force wind warning. Wind advisories and high wind warnings are also in effect for nearly 30 million people in inland areas across nearly the entire state of California from Redding to San Diego.
Officials are strongly warning against travel, especially in the mountains as the storm is forecast to drop between two and three inches of snowfall in the Sierra Nevada through Tuesday, making travel extremely treacherous along the Nevada-California border, especially in mountainous areas.
“Dangerous wind gusts are expected to produce whiteout conditions making travel above 5,000-6,000 feet ‘near impossible,'” the weather service said.
Some 150,000 customers are already without power in California, a number that is projected to grow as sustained 60 mph winds and 95 mph gusts cause havoc in the mountains, downing trees that get tangled in power lines, knocking out electricity and causing electrical hazards, forecasters and other officials warned.
The severe weather prompted NASCAR and the PGA to reschedule professional sporting events over the weekend.
NASCAR moved up the Busch Light Clash in Los Angeles from Sunday to Saturday night, and the PGA Tour announced it would move Sunday’s final round of the Pebble Beach Pro-Am golf tournament to Monday.
This storm — coming in the wake of another wintertime event that brought record rainfall to a large swath of California, including Los Angeles — is slower and expected to stall as it moves onshore, bringing much more rain that the first system did.
The central and southern California coastlines are expected to see the most significant rain and flooding, including in the Los Angeles and San Diego metro areas.
“This damaging flooding will be a threat to lives and property,” Eric Schoening with the National Weather Service said at a news briefing Saturday. “Please, if you come across a flooded roadway, we urge you to turn around, don’t drown.”
Schoening added that many roads could flood and creeks, rivers and streams will rise, causing the potential for mudslides and landslides.
Some 8,500 personnel, including swift water and helicopter rescue teams, have been deployed statewide to respond to emergency calls for help, according to Nancy Ward, director of the California Governor’s Office of Emergency Services.
“These next storms are going to be impactful and dangerous,” Ward said at a news briefing Saturday. “They’re the most dangerous natural disasters that we have, killing more people from storm damages and flooding than wildfires every year.”
More than 7 million sandbags have been prepared and plenty of rescue equipment is on standby, she added.