With no freeze likely overnight and rain forecast on Friday we can expect natural avalanche activity to continue. As temps drop on Sat and sunday, Avalanche activity will decrease.
Weather Forecast
Well here comes another blast of winter. Up to 50cm of new snow is expected over the next few days with freezing levels around 2300m. This lack of freeze at lower elevations will trigger another round of natural avalanche activity at lower elevations on all aspects. THe next few days will not be the time to get out skiing.
Avalanche Summary
Lots of loose wet, and wet slabs up to sz 3 have been observed over the past 24hrs. THese slabs have been occuring on all aspects and failing down to ground in many areas.
Snowpack Summary
The warm temps are starting to penetrate deeper into the snowpack. Isothermal snow is now being found up to treeline in some areas. Above this, expect to have surface crusts that break down later in the day resulting in some corn snow, Remember though what goes up must come down and you dont want to be wading through isothermal snow back to the trailhead.
Problems
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.
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.
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.