It’s been a snowy March so far in southern Idaho. More than seven inches have fallen in Boise, about 50 inches were recorded in the last week at the Pebble Creek Ski Area near Pocatello, and Sun Valley saw about 30 inches.
The storms brought about a week of considerable or high avalanche danger, with several reports of large avalanches in central Idaho, some hundreds or thousands of feet wide.
Today, the Sawtooth Avalanche Center dropped its risk level in one of its three zones — around Banner Summit— to moderate. The other areas remain "considerable," or 3 out 5 on the danger scale.
In particular, slopes that didn’t have as much snow before this week could be more likely places to trigger avalanches, said Ethan Davis, an avalanche specialist at the Sawtooth Avalanche Center. That includes mountains around the Wood River Valley.
On a hillside near Hailey Thursday, Davis dug deep into the snow and found about two feet of fresh powder from this week on top of a crusty wind-scorn layer. Below that was a section of older, loose snow called facets.
"[It] kind of exactly looks like rock salt or some large grain, sugary crystals that aren’t bonded well together," he said.
That unstable underlayer is what can fail and lead to slides. It’ll harden over time, Davis said, but will likely still be a concern next week, too.
Next Tuesday, the Friends of the Sawtooth Avalanche Center and the Sun Valley Company are hosting a free introduction to avalanches presentation in Spanish. The nonprofit believes this is the first public presentation of its kind in the U.S.
Find reporter Rachel Cohen on X @racheld_cohen
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