Public Bulletins will no longer be provided for the 2013/14 season however avalanche hazard will persist later this year with an above average snowpack. Contact Visitor Safety at WLNP for help with safe trip planning in the spring and summer seasons.
Weather Forecast
Watch for periods of warming in the form of sun or rain to weaken the surface crusts. If above freezing conditions persist through overnight periods the poor recovery of surface crusts and further heating may affect deeper layers. Spring storms will undoubtedly bring additional snow to the area: watch for new storm and wind slabs to form.
Snowpack Summary
Melt freeze cycles have created surface crusts on all but high North facing slopes. As new snow accumulates over these crusts watch for storm slab and wind slab problems to arise. Cornices have continued to grow with recent storms. The midpack and buried crusts provide strength over the weak basal facets in most areas with deep snowpack values.
Avalanche Summary
Recent local avalanche activity has included loose wet events associated with heating in the form of sun or, at lower elevations, rain. On the larger scene, large events failing to the basal layers continue to be reported as the snowpack loses strength with heating. Cornices and smaller avalanches are potential triggers for this type of event.
Problems
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.
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.
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.