CALIFORNIA: Thousands of Southern Californians fled their homes on Monday as a powerful rain storm that could cause flash floods and trigger mudslides soaked steep slopes where a series of intense wildfires burned off vegetation last month.

Heavy downpours that could produce more than 2.5cm of rain per hour were expected through Tuesday evening, forcing officials to order or advise Ventura, Santa Barbara and Los Angeles county residents who live near where wildfires burned to evacuated their homes.

“Recent burn areas will be especially vulnerable where dangerous mud and debris flows are possible,” the National Weather Service (NWS) said in a statement.

Property owners stacked sandbags in devastated northern wine country areas.

Forecasters issued a flash flood watch for parts for Sonoma and Mendocino counties north of San Francisco, warning that heavy rainfall could trigger mudslides in areas devastated by October wildfires.

The blazes levelled entire neighbourhoods, killing 44 people and destroying more than 8,900 homes and other buildings.

“City crews are actively driving around looking for signs of any flooding, mudslides, things of that nature. They are making sure water is flowing, making sure debris clogging storm drains or gutters is cleared up,” said Santa Rosa Assistant Fire Marshal Paul Lowenthal, who encouraged residents near burned areas to have evacuation plans in case they need to flee.

“The fire damaged a significant amount of trees and although a lot of the trees have been cut down and removed, there are still a lot of trees that could be a concern,” he said.

Several December wildfires, included a blaze known as the Thomas Fire which was the largest in the state’s history, burned away vegetation that holds the soil in place and baked a waxy layer into the earth that prevents water from sinking deeply into the ground.

About 30,000 residents were under evacuation orders or advisories on Monday, ABC news reported.

“I’m just tired. I can’t seem to get my life kick-started,” Teri Lebow, whose Montecito, California was damaged by the wildfires, told the Los Angeles Times.

The storm system was expected to produce 10-18cm in the foothills and mountains with 23cm in isolated areas.

Seven centimeters to 61cm of snow was also forecast for higher elevations, the National Weather Service said.

A yearslong drought eased in California last spring, but Northern California had a dry start to winter and hardly any measurable rain has fallen in the south over the past six months. The extremely dry conditions and high winds last year led to some of the most destructive blazes on both ends of the state.

Now, the storm coming in from the Gulf of Alaska could dump up to 12cm on Northern California areas still recovering from fires before clearing up by Tuesday evening, National Weather Service meteorologist Steve Anderson said.

“Everything is soaking into the ground at this time, but if it gets very heavy, it could trigger a flash flood warning,” Anderson said.

In Southern California, about 21,000 people were evacuated from neighborhoods beneath hillsides laid bare by the state’s largest wildfire and other recent blazes amid fears of flash floods and debris flows.

Robert Lewin, director of the Santa Barbara County Office of Emergency Management, urged residents of Summerland, Carpinteria and Montecito to leave by midday.

The hillside communities were evacuated last month as the massive Thomas Fire raged. Evacuations also include homes near other burn areas dating to 2016.

“Creeks that normally would be dry would turn into raging rivers of mud and debris and large rocks and trees,” Lewin said. “These can be quite damaging. They’ll destroy roads, they’ll take out homes.”

Agencies