Persistent Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible
- Size
- 1.5–2.5
Triggering an avalanche remains possible on weak snow buried within the snowpack's top 2-4 feet. Togwotee's snowpack is characterized by a thick layer of weak, sugary snow buried near the base of the snowpack on all aspects and elevations. This problem is most sensitive on steep, rocky, and wind-affected slopes on the north half of the compass. Watch for thin spots in the snowpack where weak layers are easier to impact, and trench your sled track into the snow or probe to identify these areas. Multiple tracks on a slope are not an indicator of stability with this avalanche problem, particularly as we see more warming and sunshine each day. Watch for slopes with cornices overhead. Warm temperatures could cause cornices to collapse unexpectedly and act as a large trigger on slopes below. Use caution in steep terrain and give yourself a wide margin for error on slopes with high consequences or around terrain traps.
This persistent slab avalanche was snowmobile-triggered on an East aspect at 9000'.
(3/17/2024)