Solar radiation may trigger avalanches which are unanticipated by shivering ice climbers in the valley below.
Weather Forecast
No new snow is forecast before the weekend. Temperatures will remain very cold and cooling further overnight to the -30C range at the icefields. Solar radiation will warm south facing slopes and add to the inversion which is already well established. Winds are generally light from the north and west.
Snowpack Summary
The snowpack is well settled with a very supportive mid-pack above 1,900m. Within this elevation range a concerning weakness can be found consisting on surface hoar and or facetted grains. This may be found 30-70cm down. Currently a failure is hard to trigger. Solar facing slops below 1,900m are melting and a suncrust is forming.
Avalanche Summary
No new natural avalanches were observed or reported. Visibility was excellent under blue skies. Solar radiation may trigger avalanches which are unanticipated by shivering ice climbers below.
Confidence
The weather pattern is stable on Thursday
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.
Persistent Slabs
Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.