Persistent Slabs
- Alta montaña
- Límite del bosque
- Bajo el límite del bosque
- Probabilidad
- Possible
- Tamaño
- 2–3.5
Two weak layers of surface hoar and facets exist deeper in the snowpack.
More snow and warm temperatures will promote storm slab development.
Be cautious in areas where the surface snow feels heavy and cohesive.
Two weak layers of surface hoar and facets exist deeper in the snowpack.
New storm slabs have been building with continued snow and warm weather. They are resting on a weak layer of facets and in places surface hoar. This could mean they will be more reactive and slower to bond.
Basal facets remain a concern in steep, rocky alpine features with thin-to-thick snowpack transitions.
A natural storm slab cycle was reported on Sunday up to size 2, on all aspects and elevations. All of them failed on a weak layer of facets.
Earlier in the storm on Wednesday, two persistent slab avalanches (size 1 and 2) were remotely triggered by skiers in the Northern Selkirks. These avalanches occurred on north aspects at treeline.
20 to 30 cm of surface snow is now resting on a variety of old snow surfaces including faceted snow, surface hoar and firm wind slabs in open terrain at treeline and above.
Down 60 to 80 cm a crust, facet, and/or surface hoar layer exists.
130+ cm down another surface hoar layer exists that was buried in early December. This seems to be of most concern above 2000 m where a robust crust doesn't exist above it, or in shallow snowpack areas.
Monday Night
Cloudy with 5-10 cm of snow, south alpine wind 10-50 km/h, treeline temperature around -4 °C.
Tuesday
Cloudy with up to 5 cm of snow, southwest alpine wind 10-40 km/h, treeline temperature around -2 °C, freezing level 1400 m.
Wednesday
Mix of sun and cloud with up to 5 cm of snow, southwest alpine wind 20-40 km/h, treeline temperature around -2 °C, freezing level 1400 m.
Thursday
Cloudy with up to 5 cm of snow, southwest alpine wind 10-30 km/h, treeline temperature around -1 °C, freezing level 1400 m.
More details can be found in the Mountain Weather Forecast.