The snow kept falling in the Cajon Pass through the early morning hours and started sticking to the ground.
Along the Grapevine, California Highway Patrol officers had to escort vehicles because of the winter weather.
"We did some pacing over the freeway between the 138 and also Grapevine Road, and we just do that to slow the traffic down," said CHP Officer Adriaan Garcia.
"Our main problem we had this morning was some big rigs going up in the community area where it's really cold and icy, and they were getting stuck in the roadways and we had to have some patrol units out there, just doing traffic control," said Garcia.
"It's a little icy, but other than that, it's a little slick coming down the hill," said one driver.
CHP expects the overnight snow to melt Monday. The melted snow is expected to freeze overnight when temperatures drop. More dangerous driving conditions could follow.
All schools in the Rim of the World Unified School District were closed Monday due to inclement weather. It was supposed to be the first day back for students after winter break.
Southland communities also dealt with strong winds. A high wind warning was issued until 4 p.m. for the Los Angeles County mountains, excluding the Santa Monica Range. A wind advisory was issued until 10 p.m. Monday for the Valleys and Inland Empire.