Ferocious winds and heavy rain are being driven into California by an offshore bomb cyclone, threatening to trigger more floods while raising the risks of mudslides and blackouts across the state.
(Bloomberg) — Ferocious winds and heavy rain are being driven into California by an offshore bomb cyclone, threatening to trigger more floods while raising the risks of mudslides and blackouts across the state.
“We anticipate that this may be one of the most challenging and impactful series of storms to touch down in California in the last five years,” Governor’s Office of Emergency Services Director Nancy Ward said at a Wednesday briefing in Sacramento. “If the storm materializes as we anticipate, we could see widespread flooding, mudslides and power outages in many communities.”
Governor Gavin Newsom declared a statewide emergency ahead of the storms, a move that provides additional authority to rapidly deploy aid where needed. Some California National Guard units have been called in to assist. California’s emergency operations center is on its highest level of alert.
Rain is falling across Northern California while strong winds are forecast to rake the region by midday Wednesday, said Hannah Chandler-Cooley, a National Weather Service meteorologist in Sacramento. The Sierra Nevada mountains could see as much as 3 feet (0.9 meters) of snow through Thursday.
“It is a pretty strong system for most of Northern California,” Chandler-Cooley said.
A massive Pacific storm has intensified so rapidly it has become what meteorologists call a bomb cyclone and brings hurricane-strength winds that are driving a deep ribbon of moisture off the ocean into California. A similar band of torrential rains, known as an atmospheric river, swept ashore last week, killing at least one person. A subsequent stream will hit this weekend, followed by another early next week, adding to the trouble.
“These little breaks will be few and far between, there is not going to be much recovery time between these atmospheric rivers,” Andrew Orrison, a forecaster at the US Weather Prediction Center, said Wednesday in an interview. “These additional events are going to pile up and exacerbate the situation out there.”
The bomb cyclone will remain offshore and weaken, Orrison said, though it’ll continue to steer moisture and winds ashore.
The storm has prompted evacuations in Santa Cruz County. The high winds and heavy downpours, combined with saturated ground from prior rainfalls, will likely lead to mudslide and debris flows along with more power outages, according to Orrison. More than 49,800 homes and businesses across California are without power as of 12:43 pm local time, according to utility tracking site Poweroutage.us.
The latest storm will spread southward across the state, adding to heavy rain across Los Angeles. As much as 4 inches of rain could fall, with up to double that amount in some isolated mountainous areas, according to the weather service.
“Significant flash flooding and debris flows are possible, especially in and below recent burn scars,” the agency said.
State officials have prepositioned emergency crews in eight counties to respond to flooding and potential mudslides in burnt areas that suffered wildfires in recent years and urged residents in those areas to be ready to evacuate quickly.
The Governor’s Office of Emergency Service has also deployed 14 incident management teams units, five fire trucks, two helicopters and a swift water rescue team to Sacramento, which is expected to see heavy rainfall through Thursday. Some communities in southern Sacramento County were flooded over New Year’s when levees failed and washed out roads and farmland.
–With assistance from David R. Baker.
(Adds comments from state officials starting in second paragraph.)
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