For the last two days, a colossal, coursing stream of super-soaked subtropical air has been pummeling California with record-shattering amounts of moisture.On Thursday, Palm Springs got eight months’ worth of rain in as many hours.In San Diego and Los Angeles, brown water thick with desert dust flooded streets, triggered mudslides, and opened up sinkholes.The 300-mile-wide, 1,000-mile-long atmospheric river that carried all this precipitation is starting to dry up, and the worst of the drench-fest is over.It’s a meteorological term of art that hasn’t yet cracked the pop cultural lexicon, unlike some of its flashier cousins—the polar vortex, bomb cyclone, and fire clouds, to name a few.But it’s only been in the last decade or so that scientists have learned enough about this type of weather system to tell the difference between beneficial, run-of-the-mill storms that keep water reserves full and disastrous storms that overwhelm dams, levees, and reservoirs, like the one that pummeled California this week.
The 9,000 person town to the east of Santa Barbara has been empty since Tuesday, when mandatory evacuations forced residents out of their homes for the fifth time in four months.This week it was a channel of tropical moisture called the Pineapple Express, dumping bands of intense rain and triggering flash floods throughout Southern California.In January it was a once-in-a-200-year storm that dropped half an inch of water in five minutes, unleashing massive mudslides that ripped houses from their foundations and killed 27.To some, Montecito might just seem like a town hit by a string of superlatively bad luck.In fact, it’s what he would call a “textbook “atmospheric river.“But it’s aimed directly at these burn scar regions which are incredibly vulnerable to flooding and debris flows.”
California residents, brace yourselves: an atmospheric river could bring multiple inches of rain to central and southern parts of the state over the next few days.Read on for a look at the meteorological phenomeonon -- and what to expect from the storm.An atmospheric river is a huge plume of subtropical moisture.“Atmospheric rivers are relatively long, narrow regions in the atmosphere – like rivers in the sky – that transport most of the water vapor outside of the tropics,” the National Oceanic and Atmospheric Administration (NOAA) says.“When the atmospheric rivers make landfall, they often release this water vapor in the form of rain or snow,” according to the agency.They may also bring severe precipitation and destruction, though “most are weak systems that often provide beneficial rain or snow that is crucial to the water supply.”
Error loading player: No playable sources foundAn atmospheric river is scheduled to cause severe rain and possible flooding in parts of California over the next few days.But what is an "atmospheric river" anyways?Rivers don't just exist on land.They can form in the sky, too.Instead of liquid water, they're concentrated bands of water vapor.
A dramatic new satellite image shows this “atmospheric river” as it extends from Hawaii to the US West Coast.They may float up in the sky, but atmospheric rivers are aptly named.Extending for hundreds of miles, these narrow columns of water vapour can channel more water than flows through the mouth of the Mississippi.When atmospheric rivers make landfall, they often release their soggy cargo in the form of rain or snow.Sometimes called the “Pineapple Express,” these enormous plumes originate in the tropics and follow a path towards large landmasses.Since early October, and after nearly five years of drought, California has faced an onslaught of atmospheric rivers.
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