Persistent Slabs
- Alta montaña
- Límite del bosque
- Bajo el límite del bosque
- Probabilidad
- Possible
- Tamaño
- 2–3
The fact that we have not observed or received reports of avalanches releasing since Sunday is evidence that triggering a slab avalanche is becoming less likely. But—and there's always a but—that does not mean it is impossible to trigger 1-3 foot thick slabs. The persistent weak layers (facets, surface hoar, and crust+facet combinations) below the recent storm snow and deep in the snowpack are adjusting to the weight of last week's big storm, but we cannot completely trust them. Where are you most likely to trigger avalanches large enough to bury people today?
- Wind-loaded terrain: Slopes where the wind formed drifts and/or stiffened the snow surface.
- "Primetime" slope angles: Slopes around 35-45 degrees in steepness.
- Southerly facing terrain: Much of the recent avalanche activity involved crusts and facets just below the recent storm snow. These layers appear to be slower to stabilize on SW-S-SE aspects than the weak layers on shadier slopes.
Recognize that it remains possible to trigger large avalanches before committing to skiing or riding in large or consequential avalanche paths. If you don't want to take on that much risk, stick to gentler slopes.
ADDITIONAL DISCUSSIONLast night's snowfall and wind may have formed thin, isolated wind slabs near ridgelines in exposed terrain. While these slides should not be large enough to bury people on their own, there's a chance a small avalanche could trigger a larger, deeper slab as it travels downslope.