.FOR CALIFORNIANS it seemed like familiarity. In 2014 a march of hurricanes, sustained by climatic streams, killed a minimum of 21 individuals as well as created nearly $5bn-worth of damage all over the condition. On February 4th this year the same type of tornado once more created chaos. Hurricane-strength winds buffeted the central shore near Big Sur. In Los Angeles celebs were soaked as they got to the Grammy honors' welcome mat. Mansion houses in the Hollywood Hillsides were covered in mud. A minimum of three people have perished. What are actually atmospheric streams, and are they a danger past California?