Daniel Swain for Reuters — California faces drenching rains from back-to-back atmospheric rivers

UCLA climate scientist Daniel Swain discusses California’s back-to-back atmospheric rivers for Reuters, sharing how these storms, products of vast airborne currents of dense moisture, are expected to drench much of the state in heavy rains and possibly trigger widespread flooding. Swain notes that the storms, also fitting the definition of a “Pineapple Express” originating from warm, subtropical waters around Hawaii, bring an abrupt change for California after a period of record, late-January warmth.

“Suffice it to say there will be some flooding in Southern California,” Swain said. “The question is whether it is the unremarkable street flooding we see in any big rainstorm or something considerably more significant than that.”