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More Rain Heading for Southern California, Heightening Flood Risk
More rain was forecast for the Los Angeles Area on Friday, adding to wet weather that prompted emergency declarations across the state.
by https://www.nytimes.com/by/dan-watson, https://www.nytimes.com/by/jacey-fortin · NY TimesSouthern California will receive more rain on Friday after several days of downpours, adding to the risk of flooding before the weather improves, forecasters said.
A new wave of precipitation arrived Thursday night and was expected to last until Friday afternoon, bringing another inch or so of rain to Los Angeles, and twice that to the nearby mountains.
The National Weather Service said there was a moderate risk of excessive rainfall in parts of Southern California, noting that even modest additional rainfall could worsen flooding in saturated areas.
Parts of southwestern California, including Los Angeles County, were under a flood advisory, with a less-serious flood watch for Ventura, Santa Barbara and San Luis Obispo Counties.
Elsewhere in the state, a winter storm warning was in effect over the Sierra Nevada Mountains, with several feet of snowfall expected in parts. There were avalanche warnings around Mammoth Mountain and Lake Tahoe.
Evacuation orders for some Los Angeles County burn-scar areas were extended through early Friday afternoon, according to the Los Angeles County Sheriff’s Department.
Mayor Karen Bass of Los Angeles said in a Thursday night statement that a limited number of evacuation orders remained in effect in Los Angeles, while those living in three areas near burn scars left by the January wildfires were being warned they might have to evacuate.
Friday’s rain is expected to be lighter and briefer than the earlier waves, with improving conditions anticipated by the evening, though spots of foggy weather could make driving difficult. Rain should begin to taper off later Friday as a cold front clears the region.
The additional rain will add to what has already been record-setting holiday weather. Downtown Los Angeles recorded 2.59 inches of rain through midday Thursday, making the Christmas Eve-Christmas Day period the wettest since 1971, according to the Weather Service.
Flooding disrupted travel and prompted evacuations across the region. Some residents spent Christmas Eve in evacuation shelters after the authorities ordered mandatory evacuations in parts of Orange, Ventura, Los Angeles and San Bernardino Counties. Gov. Gavin Newsom declared a state of emergency on Thursday in those counties as well as in Riverside and Shasta Counties.
The hardest-hit area in California this week was Wrightwood, a ski resort town of 5,000 in the mountains of San Bernardino County that was battered Wednesday by storms. Conditions remain so treacherous that the local power company told residents that an outage there would continue into next week, said Chris Reid, a contractor who lives in town.
In San Diego, a tree branch crushed and killed a person during the storm, according to the San Diego Fire Department.
The heavy rain is the result of a series of atmospheric rivers — large plumes of moisture drawn from the ocean — that have been flowing over California for the past week. Climate change also plays a factor: A warmer atmosphere holds more water, making intense rainstorms and flooding more common, and heaping one threat on top of another.