Southern California Faces New Flooding Risk on Heavy Rain, Snow

A powerful Pacific storm is bringing heavy rain and snow to Southern California, raising the risk of more flooding to a region already inundated by weeks of torrential downpours.

(Bloomberg) — A powerful Pacific storm is bringing heavy rain and snow to Southern California, raising the risk of more flooding to a region already inundated by weeks of torrential downpours.

“The rain will pick up in intensity throughout the day,” said Ashton Robinson Cook, a meteorologist with the US Weather Prediction Center. He said it’s likely to be the last big California storm for March.

The heaviest rainfall will be Tuesday, though the storm will linger through late Wednesday as it pushes into Nevada and Arizona. As much as 4 inches (10 centimeters) could drop throughout California’s coastal areas and valleys, while up to 6 inches could fall in lower elevations of the coastal mountains and Sierra Nevada range. Mountain peaks could see more than a foot of snow. The deluge raises the threat of floods in areas where more than 17 million people live in California and Arizona.

Winds could reach tropical-storm strength of 40 miles an hour (64 kilometers an hour) or more in many areas across Southern California, with gusts of at least 75 mph in the mountains through Tuesday, according to the National Weather Service.

California has been drenched by a series of Pacific storms known as atmospheric rivers since late December, bringing flooding rains and record snowfalls across the Sierra Nevada and other mountains. At least 21 people have died and billions of dollars in damages and losses have mounted from collapsed roads, inundated homes and power outages.

Read more: California’s Crippling Drought Is Almost Over After Big Storms

Because the latest storm is expected to pack more snow than rain, it’s likely to cause less damaging storms than last week’s system, according to Robinson Cook. That storm was warmer, causing mountain snowpacks to melt and create a runoff that overwhelmed streams and flooded towns in the valleys. 

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