Chain controls are in effect on both Highway 50 and Interstate 80 in the Sierra. Drivers are being urged to avoid traveling up the mountain for the time being.

The winter storm that delivered measurable rain to Southern California will offer a brief break to some parts of the region overnight before ramping up again on Christmas Day.

California officials and weather forecasters urged holiday travelers to avoid the roads on Christmas Eve and Christmas Day ahead of a series of powerful winter storms that threatened to slam the state with relentless rains, heavy winds and mountain snow through Friday.

An atmospheric river will slam into California Christmas week, bringing heavy rain and flooding concerns. Across Southern California, communities are preparing for the storm.

An even more potent atmospheric river-fueled storm is on a collision course with California after a first storm triggered deadly flooding and evacuations over the weekend in Northern California.