Persistent Slabs
- Alpin
- Limite forestière
- Sous la limite forestière
- Probabilité
- Possible
- Taille
- 2–3
Large avalanches released on buried weak layers in northerly alpine terrain last weekend. Similar avalanches could be triggered going forward.
Around 10 to 20 cm of snow may overly various weak layers. Assess for slab formation and use particular caution in any consequential terrain.
Large avalanches released on buried weak layers in northerly alpine terrain last weekend. Similar avalanches could be triggered going forward.
New slabs may have formed from recent snow and strong wind. These slabs will be particularly touchy where they rest on weak surface hoar crystals on shaded aspects.
We haven't received recent reports of avalanche activity.
Last weekend, the reports here and here describe recent large avalanches that released on buried weak layers on northerly alpine terrain.
Looking forward, we suspect that slabs forming over surface hoar crystals on northerly aspects could be reactive to human traffic. It also remains possible to trigger large avalanches on northerly alpine terrain.
Please share your observations to the MIN!
Around 10 to 20 cm of recent snow overlies surface hoar crystals on shaded aspects and a melt-freeze crust at lower elevations and on sun-exposed slopes. Recent strong wind may have formed deeper deposits in lee terrain features.
We have limited snowpack information, but this report suggests a generally weak lower snowpack with various potential layers of concern, which recently produced large avalanches.
Thursday Night
Cloudy with 1 to 3 cm of snow. 30 to 40 km/h southeast ridgetop wind. Treeline temperature -4 °C. Freezing level 500 m.
Friday
Cloudy with 1 to 3 cm of snow. 10 to 20 km/h south ridgetop wind. Treeline temperature -2 °C. Freezing level 700 m.
Saturday
A mix of sun and clouds. 10 km/h south ridgetop wind. Treeline temperature -1 °C. Freezing level 1100 m.
Sunday
Cloudy with 1 to 3 cm of snow. 20 km/h southeast ridgetop wind. Treeline temperature 0 °C. Freezing level 1200 m.
More details can be found in the Mountain Weather Forecast.