Heavy rain hit parts of Los Angeles County early Monday,causing a flash flood advisory to be issued over a wide swath of the region after midnight.

As workers prepared for their Monday morning commute, they were met with the 5 Freeway through the Grapevine being shut down due to snow and no estimate on when it would reopen. The 101 Freeway in downtown was reopened at 6 a.m. after being closed for flooding.

Pacific Coast Highway in Malibu was also closed, along with several other canyon roads including Topanga Canyon.

Between one-fifth of an inch and 1 inch of rain has fallen so far across the region since the storm began Saturday night, an additional one-tenth of an inch to half an inch is expected.

Mud, rock and debris flows, which forecasters say could affect roads and homes in and below the burned areas, continue to be a concern through Monday as heavy, localized rainfall is possible.

In the eastern part of L.A. County, bouts of heavy downpours and hail were still possible through Monday morning, the National Weather Service said. But the biggest concerns remain on the hillsides.