If the forecast holds true we will see another natural cycle start. There is a potential for large avalanches given the amount of new snow and the overall touchy snowpack. Avoid big features and limit exposure to avalanche terrain.
Weather Forecast
Another system will roll our way over night. This new storm is predicted to bring another 40cm over the next 3 days. As usual, the alpine winds will rise to the 100km/hr+ range as the storm plays out. Ridge winds will be less, but still in the ideal range for windslab development. The westerly flow will remain a constant for the next while. The front is another warm one, we can expect daytime highs of -6.
Avalanche Summary
Numerous avalanches were noted today in alpine and treeline elevations. The majority of the avalanches appeared to come down late yesterday or last night. Sizes ranged from 1 to 2.5 and were more prevalent on NE-SE aspect. Treeline avalanches had surprisingly long propagations given the slab density.
Snowpack Summary
Significantly more wind effect in the alpine today. Crossloading was evident in most alpine gullies as were some new cornices. The alpine storm slabs have matured into windslabs that will linger for some time. The underlying surface is a volatile mix of facets and surface hoar in isolated areas. At treeline, the storm snow has settled into cohesive slabs that now have enough stiffness to propagate and be a concern. Below treeline still has a remarkably weak base with difficult trail breaking at the lower elevations. The snowpack has kept its spooky, unsupported feel. Lots of cracking and whumphing in open areas at all elevation. Snowpack confidence is low at the moment and that confidence will disappear all together as new snow is added into the mix. Snow depths are 155@Burstall Pass and 102@Burstall Parking Lot.
Problems
Storm Slabs
Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-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.
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.
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.