An Atmospheric River blasted the Eastern Sierra last year, resulting in one of the heaviest snowfall years on record and the second longest ski/snowboard season ever for Mammoth Mountain.
So what is an Atmospheric River anyway?
An Atmospheric River is a river of moisture in the sky that brings forth a lot of precipitation and if it’s cold enough that means lots of snow. For the jubilant mountain folk of California, this term has been rather obsolete because they typically happen once a decade with the last atmospheric river hitting northern California in 2005-2006.
From a local's perspective, what this meant was weeks (and weeks) of non-stop snow, ice and even rain in the latter part of the season. Flights were canceled. Highways were closed. And when the mountain wasn't on weather-hold, it meant pretty much every day was a pow day. The backcountry was a glorious escape, made the most accessible it had been in years, thanks to the deep snowpack. In the spring and summer, it meant serious flooding as the snow melted.
Will this year see more of the same? According to the Farmer's Almanac, the West will see a return to "normal precipitation" levels. "This is not to say that there won’t be occasional bouts of heavy precipitation sweeping in from the Pacific, or shots of cold air pushing south through western Canada (because what’s winter without those?), but these should be balanced out by spells of dry and mild weather," it stated.
Meanwhile the Great Lakes into the Northeast will see snowier-than-normal conditions. According to the Almanac, "...we are red-flagging the 2018 dates of January 20-23, February 4-7 & 16-19, and March 1-3 & 20-23 along the Atlantic Seaboard for some heavy precipitation."
"And for parts of the western Great Lakes, eastern Great Plains, and points south, including Arklatexoma (where Arkansas, Louisiana, Texas, and Oklahoma meet), be prepared for wide swings in the weather pendulum, from very warm to very cold, and periods of tranquil conditions mixed with occasional spells of tempestuous weather."