The first of the back-to-back atmospheric rivers has slammed into the US West Coast, packing torrential rain and strong winds, and raising the threat of flash floods and landslides.
The “ Pineapple Express” – so called because it originates near Hawai’i in the tropical Pacific – is the first of two systems expected to hit the region.
The storm made landfall on Wednesday, causing heavy mountain snow, gusty winds and Rockslides in northern California. In Saratoga, one person was injured after a tree fell on a house, according to the National Weather Service.
The Bay Area, Sacramento and San Diego are under flood watch. The storm is set to spread across Southern California on Thursday.
The second storm in the series will arrive in California over the weekend and has the potential to be much stronger,
Models suggest it could intensify as it approaches the coast of California, a process called bombogenesis in which a spinning low-pressure system rapidly deepens.
The California Governor’s Office of Emergency Services activated its operations centre and positioned personnel and equipment in areas most at risk from the weather.