.FOR CALIFORNIANS it felt like familiarity. In 2014 a procession of storms, fed by atmospherical streams, eliminated a minimum of 21 folks and resulted in virtually $5bn-worth of damage around the state. On February 4th this year the very same type of tornado once again wreaked havoc. Hurricane-strength winds buffeted the central coast near Big Sur. In Los Angeles famous people were saturated as they came to the Grammy honors' ceremony. Mansions in the Hollywood Hills were actually covered in dirt. A minimum of three people have actually perished. What are actually atmospheric waterways, and are they a threat beyond The golden state?