Avalanche forecast

Silver Valley & Bitterroot Mountains

Idaho Panhandle Avalanche Center
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Avalanche danger

Sat
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
1 · Low
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Highlights

Strong winds have continued to build wind slabs on the lee sides of ridges and wind exposed terrain features, while an ice lens and various interfaces add complexity to the upper snowpack. Evaluate for stability before committing to steep open terrain today.

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–1.5

    Recent winds are loading NW-N-E facing slopes in the upper and mid elevations. To avoid these areas, look for recent drifts, both small and large cornices, and punchy surface hardness changes. Storm snow is slowly adding up over the last  week. Moderate southwest winds and snowfall will continue through today. New snow totals could begin to add up to potential storm slab avalanches. Be mindful of slopes steeper than 35 degrees near and above treeline. Plan your route while asking questions on the recent winds and storm snow loading.

    Wind transported snow.

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Unlikely
    Size
    1.5–2.5

    The weather over past two weeks has added complexity to the upper snowpack. Various interfaces exist both above and below the rain crust/ice lens, formed on February 19th, 1-2’ from surface. The Luck Friday Crust from January is now buried 2-4’ deep. While we have not seen recent propagation, I am still skeptical of triggering a slide on these low likelihood, high consequence layers. I would definitely evaluate carefully before committing to steep terrain with consequential runouts, especially where the snowpack is shallow and near trigger points like rock bands and protruding rocks or trees.

    (3/2/2023)

    Buried grauple, Feb 19 ice lense, and various interfaces buried 50cm from surface.

Avalanche Discussion

Wind loading took place throughout the day yesterday as Micah and I toured around Goose Peak. It was puking snow sideways all day with wind howling out of the south-southwest. Strong winds, with gusts into the 40’s, transported available snow onto the lee side of ridges and terrain features like gullies. Our parked snowmachines were partially buried by wind swept snow in just a few hours. We observed cracking in drifted snow and density changes become more prevalent throughout the day.

The upper snowpack has gained complexity in the past couple weeks. Yesterday we found the February 19th rain crust buried as a blue ice lens 30 to 50cm below the surface at various elevations and aspects. A few cm above the ice lens we found a 5cm layer of well-preserved graupel, as well as various interfaces buried deeper in the snowpack. While our pit tests did not show propagation, I maintain a healthy dose of suspicion for these layers and will keep an eye on them in the weeks to come.

Overall skiing and riding conditions are decent in wind sheltered terrain with the ice lens buried 30-50cm below the surface. My biggest concern today is touchy wind slabs on our zone's biggest terrain, like Steven's Peak, where consequences of being taken for a ride are severe. Other than that, if the wind abates and the sun pokes out skiing and riding should be pretty fun.

Regions covered