DENVER – Get ready for a snowy weekend in the mountains.
An "atmospheric river" carrying a significant surge of moisture from the Pacific Ocean is expected to bring up to 20 inches of snow across Colorado's high country, beginning later this week.
The National Weather Service on Wednesday was calling for an expected 13 inches in Vail and 10 inches in Aspen and Steamboat Springs from 5 p.m. Thursday through 5 p.m. Saturday.
But the snow showers were expected to last through the weekend, with 12-20 inches of snow possible from Telluride up through Aspen and 8-12 inches in areas north of Interstate 70, according to Denver7 meteorologist Mike Nelson.
Don't expect much snow in the Denver area and across the northeast plains. Most of the moisture heading for the high country will be intercepted by the mountains, leaving only an inch or two of snow for Denver and the plains.
We'll see some scattered rain and snow showers developing later on Friday, and a chance for light snow on Saturday and Sunday. But most of the precipitation won't make it far past the mountains.
Now about this so-called atmospheric river.
The phenomenon functions, literally, as a river in the sky, carrying a large amount of water vapor – equivalent to about the average flow of water at the mouth of the Mississippi River – through a narrow column in the atmosphere, according to the National Oceanic and Atmospheric Administration.
Atmospheric rivers bring about 30-50% of annual precipitation along the West Coast. And this week, we'll see that atmospheric river reach the Colorado mountains in the form of snow.