California’s iconic Highway 1 has been closed along the coastline south of San Francisco, residents have been forced to flee their homes and rivers are on the rise as more powerful Pacific storms batter the state this week.
(Bloomberg) — California’s iconic Highway 1 has been closed along the coastline south of San Francisco, residents have been forced to flee their homes and rivers are on the rise as more powerful Pacific storms batter the state this week.
Highway 1 has been closed south of Big Sur to San Simeon, according to the California Department of Transportation website. In addition, the westbound lanes of Interstate 80 near Sacramento, the state capital, have been shut by floods and many other roads throughout the state have been closed.
The San Lorenzo River in Santa Cruz County, about 75 miles (120 km) south of San Francisco, rose 17.7 feet (5.4 meters) since Sunday after heavy rain pounded down and towns throughout the area flooded. Levels on the river probably have peaked but there will be another round of intense rain later, said Daniel Swain, a climatologist at the University of California, Los Angeles.
Emergency shelters have been opened at the Santa Cruz County Fairgrounds and at Cabrillo College, the county said in a tweet. Evacuations were ordered in in several cities.
Heavy rain started falling Sunday night in many regions, and more than 137,000 people are without power mostly in northern and central California, according to PowerOutage.us. That’s down from more than 500,000 on Sunday after an earlier storm over the weekend.
The new storm may dump 2 to 5 inches (5 to 13 centimeters) of rain in some areas and 1 to 4 feet of snow in the Sierra Nevada, a mountain range in Eastern California, said Ashton Robinson Cook, a forecaster with the US Weather Prediction Center. Wind gusts may reach upwards of 50 miles (80 kilometers) per hour in many places.
Avalanche warnings have been posted in a number of areas through the Sierra Nevada through Wednesday, according to the National Weather Service. “Any steep slopes could be dangerous,” the weather service said.
Read More: California Faces Weeks of Rain, Thanks to System Stuck in Sky
The storm is another in a series of atmospheric river events, long streams of moisture that can stretch for thousands of miles across the Pacific and then deliver as much water as flows through the mouth of the Mississippi River when they’re wrung out on California’s mountains. The storms already have caused more than $1 billion in losses and damages, according to an estimate by AccuWeather Inc. Governor Gavin Newsom said violent weather has led to 12 deaths since late December.
President Joe Biden approved a disaster declaration for California.
“This is just the middle of what has been a really wet and active pattern,” Swain said in a call with reporters.
Snow will fall by the foot in the Sierra Nevada, and a large area of the mountains could see a 1-in-50-year event, according to Enki Research.
As terrible as the rain and snow has been, there have been storms in the past that have been worse, Swain said. “This is not at the top end of what is plausible in this part of the world,” he said.
Swain said his research shows with climate change there could be even more severe storms possible that could flood wide areas of California’s Central Valley in the future. The paleorecord also has shown evidence of mega floods in California in the distant past.
For the current storm, with snow falling so fast and large amounts already in the mountains, the risk of avalanches are rising Robinson Cook said.
In addition to the rain and wind, there’s also a marginal chance of severe thunderstorms along coastal areas south of San Francisco, potentially touching off even greater destructive wind gusts and short-lived tornadoes, according to the US Storm Prediction Center.
The system will continue to unfold through Tuesday, and another atmospheric river is expected to land Thursday and Friday. The pattern that’s sending storm after storm to the West Coast probably won’t start to break up until the middle of next week.
–With assistance from David R. Baker.
(Updates first two paragraphs with road closures.)
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