Persistent Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Likely
- Size
- 2–3
Recent avalanches: We have yet to get a good survey of fresh avalanche activity following Thursday's storm. However, we expect there was a fresh round of natural avalanche activity.
The snowpack in the Summit Lake zone is weaker and more reactive than most of our other forecast areas. This is because the weak layer of faceted snow that formed in December is shallower here, maiking it easier for the weight of a person to impact the weak layer and trigger an avalanche. The most recent observation from the area noted a very reactive snowpack with multiple collapses, some of which propagating several hundred feet. This is clear, straigthforward feedback that we don't always get with a persistent weak layer, and it indicates the snowpack remains reactive and that it is still likely that a person can trigger a large avalanche.
The best way to manage this problem is to avoid traveling on or below steep terrain. Be aware that you won't always get those clear warning signs, even though the snowpack is ready to produce a big avalanche.
Wind Slabs: Easterly winds are expected to increase slightly during the day, which may build a fresh round of reactive wind slabs at upper elevations. These will likely be small today, but this is one more thing to pay attention to as you travel.