Cooler temperatures will allow for up to 20cm of snow this week but watch for warming on Thursday to bring an increase in the avalanche hazard.
Weather Forecast
Freezing levels should remain below 1900m with snow and then light snow to bring up to 20 cm by late Wednesday while west winds continue with moderate and even strong gusts . Thursday will bring a significant change with freezing levels rising to over 2500m as part of a warming trend that looks like it will continue into Friday
Snowpack Summary
Rain and solar heating created surface crusts below 2200m and to ridge top on solar slopes. 5 to 10 cm of new snow Saturday, as well as extensive amounts of snow available from last week, has been redistributed by strong Westerly winds to create extensive wind effect and slabs TL and ALP. The snowpack BTL is dwindling: not much remains below 1800m.
Avalanche Summary
It has been a fairly active week with high freezing levels driving a prolonged cycle. Storm and winds slabs that developed from last week's storms failed TL and above to size 2.5 mainly as a result continued wind loading. Extensive loose moist activity to sz 2 associated with rain or solar heating has affected many slopes mainly TL and below.
Confidence
Freezing levels are uncertain 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.
Loose Wet
Loose Wet avalanches are the release of wet unconsolidated snow or slush. These avalanches typically occur within layers of wet snow near the surface of the snowpack, but they may quickly gouge into lower snowpack layers. Like Loose Dry Avalanches, they start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-wet avalanches include point-release avalanches or sluffs. Loose Wet avalanches can trigger slab avalanches that break into deeper snow layers.
Deep Persistent Slabs
Deep Persistent Slab avalanches are the release of a thick cohesive layer of hard snow (a slab), when the bond breaks between the slab and an underlying persistent weak layer deep in the snowpack. The most common persistent weak layers involved in deep, persistent slabs are depth hoar or facets surrounding a deeply buried crust. Deep Persistent Slabs are typically hard to trigger, are very destructive and dangerous due to the large mass of snow involved, and can persist for months once developed. They are often triggered from areas where the snow is shallow and weak, and are particularly difficult to forecast for and manage.