The Sawtooth Avalanche Center based in Sun Valley begins its daily backcountry forecasts Monday.
Before the snow system dumped on Idaho’s mountains this weekend, most of the snowpack in southern Idaho dated back to late October.
Forecaster Ethan Davis said after that it was warm and dry through November and early December.
“A lot of [the snow] has melted as high as even 9,500 feet up," he said.
But mountain slopes that don’t get a lot of sun still have some of that early season snow, and those shady spots will be the most dangerous with new snow on top.
“There are lots of places where the snow is going to be falling on dirt and that will behave much differently than where the snow is falling on an old crusty and weak snowpack," Davis said.
The Sawtooth Avalanche Center’s forecasts are released every day at 7:30 a.m. throughout the winter. The forecasts cover a 2 million-acre area spanning mountains northwest of Stanley to south of the Wood River Valley.
Find reporter Rachel Cohen on Twitter @racheld_cohen
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