Landslides closed roadways across California on Friday as the Golden State was hit with more rainy weather. 

The National Weather Service in Sacramento said that a large area of moderate-to-heavy rain was moving inland from the Bay Area early Saturday morning, with widespread urban and small stream flooding expected to develop.

"Cosumnes River at Michigan Bar has exceeded flood stage and will crest at 15.5 ft by 8 pm tonight!" it noted.

The agency's Bay Area office tweeted that flood advisories there were in effect. 

OREGON, WASHINGTON HIT WITH DEADLY STORMS, FLOODING

"Peak gusts will be 30-50 mph with strongest winds over mountains. With saturated soils, even moderate winds could cause downed trees/branches, power outages, falling debris," it cautioned early Saturday.

Northern California officials warned that rivers and streams could overflow, and urged residents to get sandbags ready.

Outage tracker PowerOutage.US showed that more than 16,000 customers were without power on Saturday morning.

Humboldt County also saw roadways begin to flood, according to the National Weather Service’s Eureka office. 

Landslides had already closed routes between Fremont and Sunol, as well as in Mendocino County. 

The California Highway Patrol reported that parts of eastern Sacramento roads were impassable at times on Friday due to flooding.

'COLD-STUNNED' SEA TURTLES RESCUED IN GEORGIA DUE TO 'UNUSUAL EXTREME COLD WEATHER'

Crews cleared debris in Piercy into Friday evening.

The atmospheric river storm was expected to bring more precipitation through the day, with the potential for flooding and multiple feet of snow in the Sierra Nevada.

A winter storm warning was in effect into Sunday for the upper elevations of the Sierra – from south of Yosemite National Park to north of Lake Tahoe – where as much as five feet of snow are possible, according to the National Weather Service's Reno office. 

Flood advisories were also in effect in western Nevada.

In addition, avalanche warnings were issued in the backcountry around Lake Tahoe and Mammoth Lakes south of Yosemite.

In Southern California, moderate-to-heavy rain was forecast on Saturday.

This marks the first of several storms expected to hit California over the coming week.

The Associated Press contributed to this report.