Rain to persist as storms still batter California

About 90 percent of California's population — more than 34 million people and 10 percent of the population in the United States — were under flood watches on Monday as another severe thunderstorm slammed the West Coast after a short reprieve from heavy rains last week.

The number of deaths related to the storms had climbed from 12 to 14, state officials said on Monday.

Forecasters warned that a new wave of thunderstorms is going to be more severe.

More than 37 million people were under wind alerts on Monday in California, Nevada, Oregon, Washington, Utah, Arizona and Wyoming as hurricane-force wind gusts topping 120 kilometers per hour hit some of the states.

"This will be a fairly substantial second wave," Daniel Swain, a climate scientist at the University of California, Los Angeles, said live on YouTube on Monday morning. "What falls is going to fall quickly."

On Sunday evening, US President Joe Biden declared a state of emergency for California. It cleared the way for assistance from the Federal Emergency Management Agency to coordinate with local efforts.

The storms hitting California are caused by a barrage of atmospheric rivers, which are long, flowing regions of the atmosphere that transport water vapor through the sky.

When atmospheric rivers make landfall, they often release water vapor in the form of rain or snow.

While the atmospheric rivers continue to pummel California through this week, its most potent system was expected to arrive on Monday, the National Weather Service said.

"This storm was as bad as a couple of the hurricanes I've been through. Never in my life (as) a Californian have I felt this kind of windstorm," tweeted Carley Gomez, a meteorologist at ABC10 in Sacramento.

Search called off

Rescuers ended the search for a 5-year-old boy who was swept away by floodwaters in central coastal California, while the entire community of Montecito was evacuated on Monday as residents grappled with flooding and mudslides as the latest of powerful storms hit the state.

The evacuation order came on the fifth anniversary of a mudslide that killed 23 people and destroyed more than 100 houses in the coastal enclave of about 8,600 people.

Since Dec 26, San Francisco has received more than 25 centimeters of rain, the National Weather Service said. Mammoth Mountain, a popular ski area in the Eastern Sierra Nevada, got nearly 3 meters of snow.

The storms will not be enough to officially end California's drought, but they have helped.

Swain expects a break in the rain after Jan 18.

"That is my best guess right now, which is good because it will give the rivers in Northern California, and now in Central California, a chance to come down," he said.

Agencies contributed to this story.