A second and more powerful atmospheric river-fueled storm is set to bring potentially life-threatening flooding to Southern California from Sunday into next week after an earlier storm already unleashed record rainfall in some parts of the region.
The second atmospheric river set to hit California within days could begin lashing the state’s central and southern regions as early as late Saturday night and linger for several days.
Forecasts show Southern California, including Santa Barbara and the greater Los Angeles area, is expected to bear the brunt of this storm, with the worst flooding expected to begin Sunday.
“Chances are increasing that a lengthy period of heavy rain will develop late Saturday night and continue through most of Sunday and Monday,” the National Weather Service in Los Angeles warned.
More than a month’s worth of rain could fall across much of Southern California, with widespread rainfall totals of 3 to 6 inches expected from late Saturday to Wednesday, the weather service said. That would be in addition to the torrential rain the region saw Thursday, when the first strong atmospheric river unloaded record rainfall in several areas and triggered water rescues.
This weekend’s atmospheric river – a long, narrow moisture band that carries saturated air thousands of miles then discharges it like a fire hose – is projected to be even more powerful than the first and stall over land.
The projected deluge threatens urban flooding, mud and rock slides, flash and river flooding. Another surge of heavy rainfall elevates the risk of debris flows considerably in already-saturated Southern California soil.
“With the ground already saturated from today’s rain, onset of dangerous flash flooding will be much quicker with this next event and everyone, especially those near or in south facing mountains, needs to start preparing now for possible evacuations during or even before the storm hits,” the National Weather Service warned Thursday.
Beginning Sunday, a Level 3 of 4 risk of excessive rainfall is in place for coastal sections of Central and Southern California, including the Santa Barbara area, with a Level 2 of 4 risk along the coast from north of San Francisco to Los Angeles, according to the Weather Prediction Center.
The Level 3 of 4 threat of excessive rain will continue Monday for Santa Barbara and will expand to also include Los Angeles.
Overall, rainy conditions are expected to continue well into February as a more typical El Niño pattern kicks into gear.
El Niño – a natural phenomenon in the tropical Pacific that influences weather around the globe – causes changes in the jet stream that can point storms directly at California. Storms can also tap into an extra-potent supply of moisture from the tropics called an atmospheric river.
A ‘life-threatening flooding’ situation
Meteorologists in Southern California are sounding the alarm over next week’s considerable rainfall.
On Thursday, the National Weather Service in Los Angeles warned of the “potential for damaging, life-threatening flooding,” urging people to prepare.
Southern Californians should be ready for potential evacuations near rivers and creeks and use sandbags to protect vulnerable areas, the weather service said.
Rainfall totals are forecast to climb even higher for mountain and foothill areas in Southern California. These locations could see up to a foot of rain from the atmospheric river, according to the weather service.
Mountain travel will become treacherous in the central part of the state as heavy snow is expected, with the Sierra Nevada forecast to see up to 4 feet of snowfall.
“Residents might be stranded for several days, get extra supplies & gas,” the weather service warned.
The ominous forecast comes as Southern California reels from the round of heavy rain it endured Thursday from an earlier atmospheric river. Parts of the Pacific Coast Highway and the 710 Freeway closed as first responders carried out water rescues.
Long Beach – south of downtown Los Angeles – was heavily flooded, with social media videos showing roadways entirely underwater. Fire crews rescued some people from a few submerged vehicles, officials said, though no injuries were reported.
One person was hospitalized in stable condition after he was rescued in nearby Orange County where he became trapped in a storm channel that was inundated by heavy rainfall, fire officials said.
Thursday’s deluge dumped 2.37 inches of rain at Los Angeles International Airport, breaking the daily record of 1.55 inches set in 1960. The airport’s average rainfall for February is 2.99 inches, meaning the station received nearly its monthly rainfall for February on the first day of the month.
Meanwhile, Santa Barbara Airport saw 2.93 inches of rainfall, exceeding the daily record of 2.02 inches set in 1960. Long Beach Airport saw 2.43 inches of rainfall, surpassing its 1960 daily record of 1.45 inches.
CNN Meteorologists Robert Shackelford and Mary Gilbert contributed to this report.
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