A winter storm that could be the largest of the season is dousing Southern California.

Heavy rains are hitting the region Monday morning and will last much of the day.

The National Weather Service says gale-force winds are causing dangerous surf conditions off the coasts of Santa Barbara and Los Angeles counties.

The California Highway Patrol says the Grapevine section of Interstate 5 in the mountains north of Los Angeles is being covered with snow and travelers should expect delays.

Meteorologist David Gomberg calls it the "most significant storm so far this season."

The rains bring renewed fears of mudslides in areas ravaged by wildfires last year, including Orange County and northern Los Angeles County, where the city of Sierra Madre has warned residents they may need to leave their homes.

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