Heading into a stable weather pattern for weekend
Confidence
High - The weather pattern is stable
Weather Forecast
Friday: Mainly cloudy / Light northerly wind / Alpine temperature -9Saturday: Sunny with cloudy periods/ Light northeast wind / Alpine temperature -10Sunday: Mix of sun and cloud / Light west wind / Alpine temperature -10
Avalanche Summary
Recent reports from Wednesday in the region show explosives triggering wind slabs to size 1.5 in the alpine. There is no other recent significant activity to report.
Snowpack Summary
The storm snow from earlier this week has been redistributed in the alpine and exposed treeline by strong to extreme winds. This has left a variety of hard surfaces that may include sastrugi, wind crust and hard wind slab. This surface has now been covered by 5-10cm of new snow that fell on Thursday. In sheltered areas treeline and below 30-50cm of snow overlies the previous variable snow surface from last week, which included weak faceted snow or surface hoar. The widespread mid-November crust is typically down 1-2m in the snowpack. Recent snowpack and explosive tests have shown the crust to be unreactive, but it could remain a problem in shallow alpine start zones.
Problems
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.