As atmospheric rivers pound California, here comes the season’s ‘biggest storm’

California is having a very wet and cold winter, and atmospheric rivers are one of the reasons.

These storms have caused mudslides in the Southland, snow along the West Coast, white-out conditions in the Sierra and rain totals well beyond normal.

On Wednesday, a new atmospheric river was moving in — with fears of stream flooding in Northern California and potential mudslides in Southern California.

“It’s going to give us the biggest storm we’ve seen so far this season,” said Jimmy Taeger, a meteorologist with the National Weather Service in San Diego.

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Atmospheric rivers are long plumes of water vapor that can transport tropical moisture across the Pacific Ocean and disperse it in California.

They get their name because such storms carry so much water, they’ve been likened to a river in the sky.

A strong atmospheric river can carry 7½ to 15 times the average flow of liquid water at the mouth of the Mississippi River.

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Just a few atmospheric river events can provide West Coast states such as California with one-third to one-half of their annual precipitation.

Atmospheric rivers can also create storms with intense rainfall and flooding, triggering mudslides and sometimes leading to deaths.