Avalanche danger will rise through the day as new snow accumulates in the alpine, and moderate winds magnify loading on lee slopes. Be conservative in terrain selection and diligent in your group management.
Weather Forecast
Today expect flurries with freezing levels rising to 1700m. Up to 12cm of snow are expected, magnified by moderate to strong SW winds. On Friday, expect another 13cm with freezing levels at 1900m and moderate S winds. Saturday will be similar with another 9cm of snow.
Snowpack Summary
5cm of new snow will bury, and hide, a variety of surfaces from sun crusts to reactive windslabs. The upper snowpack is a complex mix of crusts, weak facetted snow and surface hoar. Below 1800m the snowpack is spring-like with a weak melt-freeze crust forming. Rain at lower elevations will destabilize the snowpack.
Avalanche Summary
On Tuesday skiers triggered a slab avalanche on Youngs Peak. It was on a N aspect, ~2100m, was reported to be 15-60cm deep, 30m wide and 100m long. In the region, windslabs have been triggered by riders daily causing avalanches to size 2. Whumphing continues to be reported from treeline areas throughout the park.
Confidence
Timing, track, or intensity of incoming weather system is uncertain
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.
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.