Another round of storms is on its way to flood-ravaged California, where residents are still dealing with impassable roads, overflowing rivers, inundated neighborhoods, and a levee breach that forced hundreds of people to flee.

By Sunday afternoon, parts of California's famed Highway 1 had turned into ponds, prompting authorities in Monterey County to close a section of the scenic road.

15 million people could endure flooding in California
(Photo : JOSH EDELSON/AFP via Getty Images)

The National Weather Service predicts that a new atmospheric river will slam the state on Monday, threatening heavy rain and even more flooding in central and northern California as another atmospheric river winds down.

Atmospheric rivers are long, narrow bands of moisture that, like a fire hose, can carry saturated air thousands of miles.

In California and Nevada, approximately 15 million people remain under flood warnings.

"As a result of this event, rainfall totals of 6 inches or more are possible across portions of central and northern California," CNN Meteorologist Haley Brink said on Sunday.

According to the Weather Prediction Center, the rain will begin to fall on Monday night in increasingly vulnerable areas of central California that were hard hit by rain on Friday and early Saturday.

As a result, once the steady heavy rain begins, flooding will resume quickly.

More flooding could exacerbate the situation in some neighborhoods, where recent torrential rains turned streets into rivers and damaged roads, stranding people and necessitating rescues.

Monterey County was among the hardest hit, with the swollen Pajaro River breaching a levee around midnight Friday.

According to Monterey County Board of Supervisors Chair Luis Alejo, the "worst case scenario" for the community was water gushing uncontrollably into nearby Pajaro, forcing residents to flee.

Some residents were unable to evacuate before the floodwaters arrived, and crews were still performing high-water rescues Saturday, according to Cal Fire Capt. Curtis Rhodes.

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At least two people have died as a result of the most recent California storm

On Friday, the state's tenth atmospheric river of the winter prompted evacuation orders for hundreds of people and inundated previously drought-stricken areas.

The latest storm to hit the West Coast brought additional flooding hazards to California on Friday, killing at least two people and isolating several communities amid the year's first flash flood emergencies.

According to AccuWeather, one of the two deaths associated with the storm occurred in Placer County, located in northern California, and the other in San Bernardino County, located in southern California.

On Friday, a third person was killed when the roof of a commercial warehouse and distribution facility for Peet's Coffee partially collapsed in Oakland, California.

According to Michael Hunt, spokesperson for the Oakland Fire Department, the cause of the collapse is currently being investigated to determine whether heavy rain played a direct role.

As part of the investigation, state and OSHA officials were on the scene on Friday.

The man killed was a longtime Peet's Coffee employee who was in the building with a woman who was taken to the hospital with non-life-threatening injuries.

According to officials, they were the only people in the building at the time.

A boat capsized in San Diego County on Saturday night, killing at least eight people, and the search for additional victims is still ongoing.

These deaths had not been confirmed as weather-related as of Sunday morning.

Due to the ongoing storms, President Biden approved an emergency declaration for California, which means the state will be able to access federal resources to deal with the flooding, landslides, and severe weather from what will be the state's 10th atmospheric river of the winter.

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