Avalanche forecast

Banner Summit

Sawtooth Avalanche Center
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Avalanche danger

Sun
Alpine
1 · Low
Treeline
1 · Low
Below
1 · Low
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Highlights

Be on the lookout for small, fresh wind drifts at upper elevations. As the day warms up, small loose snow avalanches could occur on very steep slopes that face the sun. Generally stable conditions exist on slopes that are protected from the wind and sun.

Avalanche Discussion

Thursday's small storm brought a welcome 6-10" of new snow to the Banner Summit zone accompanied by light to moderate northerly winds. This wasn't enough to appreciably change the avalanche danger, and the rating has remained at LOW. However, it did add a few things to the list of "minor" problems that you could encounter today, especially if your backcountry adventures take you to steep, consequential terrain:

  • Fresh wind slabs. I found that the combination of new snow and north winds had formed fresh wind drifts in this zone yesterday (photo). While relatively small and isolated, they could be enough to knock you off your feet or machine. Fresh wind slabs will be most common in upper elevation terrain. They'll be fairly easily identified by signs of wind texture at the surface or by snow that feels thicker, denser, or more cohesive than what you're finding on wind-sheltered slopes.
  • Loose snow avalanches. The new snow fell on top of slick crusts on slopes that face the sun. Today's forecasted warmer temps and sunshine could cause the new snow to come unglued from these crusts and form (relatively) small sluffs. These could occur naturally as the day warms up—pay attention to the terrain above you.

In addition to these small but fairly likely problems, keep in mind that weak faceted snow exists near the ground on shaded NW-N-NE-E facing slopes at middle and upper elevations. In this zone, it's buried beneath a very dense, 5-7' thick slab. Triggering this layer would take a dose of very bad luck, but local professionals and savvy backcountry riders are still leery of big, open, "prime-time" slopes (around 35-45 degrees) that are wind-affected and rocky.

Use extra caution around cornices, which—thanks to a very snowy/windy December—have grown exceptionally large this early season. Many observers have noticed cracks near larger cornices where these beasts are peeling away from steep ridgelines. Stepping through the surface snow into one of these cracks can lead to an awkward moment indeed.

Quote of the day: "I used to be as pure as new-fallen snow. Then I drifted." That about sums up my life, how about you?

Catch up on what happened (or didn't happen) this past week in Scott's latest Weekend Update.

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