Bomb cyclone smashes into California

A bomb cyclone slammed into California on Wednesday, bringing powerful winds and torrential rain that was expected to cause flooding in areas already battered by a succession of storms.

Authorities issued dire warnings about threats to life and property for much of the US’s most populous state, centered around San Francisco and Sacramento.

Forecasters said winds of up to 70 miles (110 kilometers) per hour and heavy rain could batter the region by Wednesday, with rain likely to continue into Thursday.

Meteorologists at the National Weather Service said there could be “widespread flooding, washed-out roads, landslides, downed trees, widespread power outages, immediate business disruptions, and worst of all, possible loss of human life”.

California Governor Gavin Newsom declared a state of emergency “to support response and recovery efforts,” while San Francisco set up an Emergency Operations Center.

Bars and restaurants were closed as the city was surrounded by the storm, with local media showing flooded streets and reports of long delays on public transport.

Dozens of flights in and out of the city were canceled or delayed, and about 60,000 homes were without power, according to the website PowerOutage.us.

Thousands of sandbags were distributed to residents afraid of flooding.

“We are very concerned about this,” Deepak Srivastava told CBS in San Francisco.

“(I) just spent the whole day putting sandbags in front of the garage at every entry point and we’re just crossing our fingers and hoping we don’t have any more damage.”

City officials said they were working around the clock to help people prepare.

“We’ve been working hard to get sandbags from wherever we can in northern California,” said Rachel Gordon, of the city’s public works department.

But she warned residents should take the storm seriously.

“If you don’t have to be out in San Francisco, please stay off the streets.”

The intense rain was caused by a combination of a bomb cyclone — a sudden, large drop in air pressure — and an atmospheric river, where moisture-laden air is drawn in from the oceans.

Up to four inches (10 centimeters) of rain was expected in the Bay Area, with twice that amount over nearby hills.

The Sierra Nevada mountain range was expected to receive up to four feet (1.2 meters) of snow.

– ‘Several storms’ –

The rain comes on top of a series of storms that have brought near-record rainfall in recent weeks.

On New Year’s Eve, parts of northern California were hit by a storm that caused landslides and power outages, as roofs split and roads flooded.

At least one person is known to have died after being trapped in a submerged car.

San Francisco recorded almost 5.5 inches (14 centimeters) of rain on December 31, the city’s second wettest day on record.

The waterlogging caused by those earlier storms would exacerbate the risk of this, meteorologist Matt Solum told AFP.

“This storm alone without the previous storms would cause localized flooding concerns and rock and mudslide concerns,” he said.

“But with the recent wet conditions, much of the rainfall that has already fallen has already saturated the ground, so any additional rainfall will run off rather than soak into the ground.”

While it’s hard to draw a straight line for this storm from human-caused climate change, scientists say a warmer planet brings more erratic weather, with wilder storms, as well as longer dry spells and the hottest.

The western United States is in the grip of a decades-long drought, with below-average rainfall leaving river and reservoir levels at alarming levels.

Solum said that while any rain is helpful in mitigating drought — a long-term issue — these back-to-back storms can be devastating because there’s nowhere for the water to go.

“It’s just the compound impact of all the storms that’s going to be the most impactful,” he said.

“Typically, we don’t see this many series of storms with this much heavy rain.”

And there is more to come.

“It will definitely continue,” he said.

“We expect another one over the weekend. And then another couple of storms potentially for next week. And maybe the week after.”