Published on : 05/01/2023 – 03:30
Tens of thousands of Californians were without power on Wednesday due to a potentially deadly “cyclone bomb”. While several roads in the western US state have already been cut, authorities fear landslides and flooding.
A “cyclonic bomb” swept over the California Wednesday January 4, bringing violent winds and torrential rains which deprived tens of thousands of homes of electricity and caused the closure of several roads, in a region already weakened by a series of winter storms.
Northern California, especially around San Francisco and Sacramento, is the region most at risk. Authorities warned of landslides and flooding, warning that this storm was capable of killing people.
Its first effects were felt Wednesday afternoon: more than 60,000 homes suffered power cuts, according to the PowerOutage site, while more than 80 flights to or from San Francisco airport were canceled, according to the Flightaware site.
In some counties in the region (Mendocino, Santa Cruz, Santa Clara), several roads were cut due to flooding, falling trees or landslides.
According to the US Weather Service (NWS), winds likely to reach 110 km / h are expected on Wednesday. Very intense rains are also expected to hit the area, with up to 10 centimeters of precipitation expected in San Francisco Bay and 1.2 meters of snowfall in the Sierra Nevada mountains. The deluge is expected to continue Thursday.
California Governor Gavin Newsom declared a state of emergency on Wednesday morning to facilitate the emergency response and streamline the reaction of the authorities in the event of an incident.
San Francisco has set up an emergency operations center and interrupted the circulation of its famous cable cars. “If you don’t have an obligation to be outdoors in San Francisco, avoid going out on the road,” warned Rachel Gordon, an official with the city’s public works department.
Bars and restaurants there remained closed on Wednesday and some residents were asked to work from home. City firefighters reported several falling trees Wednesday morning and some minor flooding, before the heart of the storm arrived. Thousands of sandbags have been distributed to residents of areas at risk of flooding.
Northern California is still suffering the effects of a series of storms. The latest swept through on New Year’s Eve and caused landslides and power cuts. At least one person has died after being trapped in their car by flooding, authorities said.
On December 31, San Francisco recorded the second rainiest day in its history since the measurement was launched, with 14 centimeters of precipitation.
Risk of flash floods
Under these conditions, the soils of the region, drained by the drought that has hit the American West for two decades, will have difficulty absorbing a new deluge, which increases the risk of flash floods.
“On its own, this storm could cause localized flooding and landslides,” said meteorologist Matt Solum for AFP. “But with the recent wet conditions… any additional rain will run down instead of soaking up the ground.”
Climate change is increasing the frequency and intensity of extreme weather events. The rain expected on Wednesday comes from an “atmospheric river,” a narrow, river-like band in the atmosphere that carries huge amounts of moisture from the tropics.
Far from being exceptional in winter, this current phenomenon is accompanied by a “cyclonic bomb”, a system capable of causing the pressure to drop suddenly, thus generating very violent winds.
According to meteorologists, the series of storms currently battering California is not about to stop. “We are expecting another one over the weekend,” announces Matt Solum. “And then potentially several storms for next week. And possibly the following week as well.”