A flood watch will go into effect Wednesday afternoon across much of Los Angeles and Ventura counties as weather officials warn about heavy rainfall and debris flows. The National Weather Service has issued a flood watch from Wednesday evening until Thursday afternoon.

Flood watches are in effect for most of L.A. County, with the possibility for flooding across the area. Schoenfeld said there’s a 30% to 50% chance of major flooding impacts in burn scar areas with concerns for mudslides, road erosion, debris flows and cars being stuck in mud.

A colossal storm is threatening to bring severe weather to much of California this week and could impact travel over the Grapevine. Here's what to know.