The aftermath of a debris flow near the Carmel/River Burn Scar in Monterey County on Wednesday.
The aftermath of a debris flow near the Carmel/River Burn Scar in Monterey County on Wednesday.
(National Weather Service)

REGIONAL PICTURE: Atmospheric river triggers debris flow in Monterey County; snow in Sierra Nevadas

The West Coast’s enormous atmospheric river stalled over Monterey County on Wednesday, triggering mudslides and threatening other areas even farther north, with the storm expected to swing southward Thursday, posing risks to parts of Southern California burned by last year’s wildfires.

Although the most torrential rains stalled over Monterey and Big Sur, weather forecasters say isolated but severe storms still threaten the area.

The storm delivered several feet of snow to the Sierra Nevada Mountains, particularly the area between Yosemite National Park and Mammoth. More snow is expected into Friday, which could help replenish the state’s water supplies diminished by dry winters, including the last three months.

The ‘atmospheric river’ has passed. Here’s how much rain the Santa Cruz area saw — and what to expect going forward.

The Bay Area and Central Coast were battered by the storm Tuesday night and Wednesday morning, with heavy rain, high winds and snow in some of the higher elevations. By Wednesday morning, 24-hour precipitation totals collected by the National Weather Service showed 5.2 inches of rain at Hearst Castle and nearly 4 inches in Carmel Valley Village.

Photos on social media showed a major mudslide in Big Sur across part of Highway 1, which had been closed Monday in advance of expected debris flows, as well as in the burn scar area near the footprint of the River Fire in Monterey County.

No debris flows had been reported in Santa Cruz County, and a Lookout story Wednesday detailed that the geography of the CZU fire scar might be limiting the risk of ones happening here.

Flash flood warnings are still in effect for much of Monterey County, including areas previously burned by the Dolan, Carmel and River fires until Thursday afternoon.

In San Luis Obispo, 1.5 to 2 inches of rain had fallen by early Wednesday morning. “Copious amounts of rain” are expected in the foothills, the weather service said, and a flash flood watch is in effect until Thursday evening.

This story originally appeared in the Los Angeles Times, a Lookout content partner.