California Big Sur Highway 1 Section Collapses Into Ocean After Storm

A portion of highway along the Big Sur coast in California suffered severe damage during this week's stormy weather.

A photo shared on Facebook by the Monterey office of the California Highway Patrol shows mud and debris on the highway near Rat Creek.

The image also shows a section of the road has been washed away. The area affected had already been closed.

The California Highway Patrol said in the post: "State Route 1 between MPM 40 and the San Luis Obispo county line continues to be impacted by inclement weather, debris flow, flooding, and slides.

"This area is closed to the public. Remain clear of the area and plan alternate routes. Please continue to exercise extreme caution on rural roads, especially at night. Please see CALTRANS website for up-to-date information on road closures. Stay safe."

The National Weather Service said the Big Sur coastline would be seriously impacted by the storm, which has been intensified by the moisture from an atmospheric river.

"Our local in-house model is showing extensive storm totals in the Big Sur hills in excess of 20 inches with a bullseye amount in excess of 31 inches," the service said.

An atmospheric river is a long, narrow, horizontal ribbon of air containing high levels of water vapour, which flows through the atmosphere like a river. It can transport large amounts of moisture and when the river makes landfall, the water vapour rises, cools and condenses, leading to heavy rain or snow.

The National Weather Service has warned of possible "life-threatening flooding and debris flows" areas affected by burn scars from wildfires and sustained downpours.

Residents in parts of San Mateo County and Santa Cruz are under evacuation orders due to a threat of mudslides.

The California Department of Transportation is working with local law enforcement to limit travel into the Big Sur area and to allow people to evacuate safely. Signs and barricades have been put up to warn people of the closure.

Last year, experts had warned that wildfires would leave parts of California facing a high risk of mudslides during the rainy season. These fires leave land barren and vulnerable to a a rapid-moving type of landslide called a "debris flow" or mudslide.

These slips are usually caused by short, intense storms and can send dirt, rocks and even homes down hillsides.

Big Sur coastline California
The National Weather Service said the Big Sur coastline would be seriously impacted by the storms George Rose/Getty Images