Wind slabs in the alpine and treeline have been easy to trigger for skiers and boarders. Be cautious when traveling above the treeline. Today is the last day of the permits for the 2012-2013 season.
Weather Forecast
Sunny with cloudy periods today, followed by cloud and snow flurries that begin tonight and through tomorrow. This should be followed by a series of weak storms on Friday and into the weekend with rising freeze lines.
Snowpack Summary
40-50cm of settling storm snow over the April 3rd crust which varies in thickness due to strong winds at tree line and alpine elevations. Below this crust in most areas the snowpack is isothermal.
Avalanche Summary
Monday, a Skier Accidental, size 3.0 on the east face of Mt Swanzy, depth 100cm, 150m wide, suspect April 3 crust. Skiers were not involved, and later the same day a Skier Accidental, size 2.0, Forever Young couloir, depth 30cm, 40m wide ran to 2/3 fan. Skier got taken down onto the fan before he managed to self arrest.
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.
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.
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.