Persistent Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Unlikely
- Size
- 2–3
Cooler, below-freezing temperatures, earlier this week, have refrozen a previously weak and saturated snowpack. Rain and heavy snow from late February have formed a strong rain crust, helping to stabilize the January Drought Layer (JDL) below. While the snowpack is improving, and triggering an avalanche in the persistent slab is unlikely, the problem isn't entirely gone. In shallow, rocky terrain or upper elevations where the rain crust is thinner, triggering the lingering weak JDL grains is still possible. Since these weak layers are now buried 2-3 feet deep, they are harder to affect on skis, but a heavier snowmobile has a greater chance of breaking through and triggering a large avalanche.
(3/6/2025)
Hiding near the treeline is an old crown. This avalanche failed in a thinner part of the snowapack, near a thin rocky cliff band.
Photo: Izzy Davis