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Human triggered avalanches are possible in middle and upper elevation terrain. Triggering a large avalanche is most likely where 1) the wind has formed drifts or stiffened the surface and 2) old, weak snow exists below the recent wind-drifted snow. The avalanche danger will increase to CONSIDERABLE tonight as the next storm brings more snowfall and wind.

You may have noticed that we did not issue an Avalanche Problem with this forecast; given the challenging access to these mountains, we are starved for information. Don't worry - we're out collecting information and dialing in the problems as quick as we safely can. In the interim, build a healthy safety margin into your trip plan. 

If you head into the mountains today:

• You can drastically reduce your risk of triggering a large avalanche by looking for and avoiding areas with a stiff slab near the surface. Actively seeking out softer snow is safer and more enjoyable but doesn't eliminate the threat of triggering an avalanche. Given the recently observed avalanches, even deceptively soft slabs have the potential to release in steep terrain.
• Weak, faceted snow was buried by recent storms on many middle and upper elevation slopes. This problem is most prevalent on NW, N, NE, and E aspects, and on some sunnier aspects at upper elevations. Here, early season snow has lingered for weeks or months. Slides may break wider than expected and can be triggered remotely—from gentler terrain above, below, or to the sides of steep slopes.
• All recent observations noted cracking, collapsing and, even remote triggering of avalanches. These are all obvious signs of instability. If you see similar signs, it is a clear indication that you've found unstable snow and should look for lower angle or softer snow in areas sheltered from the wind. If you're out today, be aware that avalanche conditions could worsen this afternoon and evening as a significant storm arrives.
• Slopes where wind-drifted or new snow fell or is falling directly on the ground are generally stable.

The season is young, the snowpack is shallow, observations are limited, and we have a lot to learn. What we do know: the snowpack contains weak snow where there's enough snow to keep your skis or sled off the ground, and this same terrain produced large avalanches over the weekend. Given the limited observations, building this uncertainty into your trip plans means including a larger margin of error. If you're out in the mountains, please submit an Observation to help us fill in the gaps!