‘If you’re unfamiliar with atmospheric rivers, or are wondering if that’s just a fancy name for “rain”, they’re actually a unique movement of moisture through Earth’s atmosphere, responsible for most of the horizontal transport of water vapour outside the tropics. These suspended moisture plumes, which can stretch 400 to 600 km wide (250 to 370 miles), have been linked to all seven floods on California’s Russian River between 1996 and 2007, and likely played a role in the ‘Snowmageddon’ event that blanketed the East Coast in 2010.’
An extraordinary atmospheric event that is erasing California’s drought with tremendous speed, but not without a price.
http://www.sciencealert.com/giant-rivers-in-the-sky-are-causing-widespread-chaos-in-california