'Atmospheric River' Slams CA With Record Rain and Snow

CALIFORNIA — As rain pummeled southern California, parts of northern California went from drought to flooding overnight as a weather phenomenon called an atmospheric river dropped several inches of rain and snow over the area.

In this case, an atmospheric river is a narrow, yet powerful, band of precipitation which picked up warm Pacific waters before letting loose over land in the form of either rain or snow — or both.

The storm drenched central and northern California with rain and snow that helped douse wildfires in the area, yet weather observers are taking a "wait and see" approach with how much of the drought conditions were quelled.

The National Weather Service called preliminary rainfall totals “staggering.”Four inches fell in downtown San Francisco, the fourth-wettest day on record.

“It’s been a memorable past 24 hours for the Bay Area as the long talked-about atmospheric river rolled through the region,” the local weather office said in an AP report. “We literally have gone from fire/drought conditions to flooding in one storm cycle.”

See photos from the atmospheric river, and the storm's aftermath.

Rainfall records were shattered, and heavy snow pounded high elevations of the Sierra Nevada. Officials said mountain areas above 9,000 feet in the Sierra Nevada predicted 18 inches of snow or more from Sunday until Monday morning.

Bruno and Julie stroll on a rainy day in Long Beach, Calif., Monday.

A man attempts to stay dry while riding along Colorado Boulevard in Pasadena, Calif., during a rainstorm, Monday.

In this photo provided by Mammoth Mountain Ski Area, snow falls on Mammoth Mountain, Monday in Mammoth Lakes, Calif.

In this photo provided by Mammoth Mountain Ski Area, falling snow collects on cars in a parking lot at Mammoth Mountain, Monday in Mammoth Lakes, Calif.

In this photo provided by Mammoth Mountain Ski Area, snow falls on Mammoth Mountain, Monday in Mammoth Lakes, Calif.

Water flows at the inflow to Lake Kaweah, a large reservoir in Three Rivers, Calif., Monday, Oct. 25, 2021.

Houseboats float on Lake Oroville, Monday in Oroville, Calif. Recent storms raised the reservoir more than 16 feet, according to the California Department of Water Resources.

In this photo provided by Mammoth Mountain Ski Area, snow falls on Mammoth Mountain, Monday in Mammoth Lakes, Calif.

Garfield Elementary crossing guard Kai Dill tries to leap across the flooding street on Peach Ave., in Clovis, Calif., Monday. A massive storm barreled toward Southern California on Monday after flooding highways, toppling trees, cutting power to about 380,000 utility customers and causing rock slides and mud flows in areas burned bare by wildfires across the northern half of the state.

A wind surfer surfs in the rain in Long Beach, Calif., on Monday.

An abandoned car is stuck in the mud on Chualar River Road as rain falls over Salinas Valley, Calif. Monday.

A vehicle negotiates standing water along Riverside drive in Toluca Lake, Calif., Monday 2021. Heavy rain moving down from Northern California is expected to hit the Los Angeles area.

A car crosses a flooded parking lot in Oroville, Calif., on Monday. A massive storm barreled toward Southern California on Monday after causing flooding across the northern half of the state.

The Associated Press Contributed to this report.