This weekends hazard hinges on snowfall amounts with anywhere between 10 to 30cm forecast. Keep an eye on how much snow actually arrives on Saturday and Sunday
Weather Forecast
Finally, some snow! An incoming system will bring 10-30cm of precipitation on Saturday and Sunday. Warm temperatures and SW winds will rapidly switch to very cold temperatures (-30 in the alpine) and E winds on saturday night. This will set up nicely for the storm to end depositing nice cold fluffy snow, with higher amounts in the front ranges.
Snowpack Summary
15-20cm settled powder has been redistributed by strong to extreme west winds in the alpine and at treeline. This sits on a variety of wind affected surfaces and a melt freeze crust below 2000m. The midpack is strong in deep snowpack areas, but the facets lingering at the bottom remain a concern in thinner areas.
Avalanche Summary
A skier controlled size 1.5 avalanche was reported on a west aspect at treeline in the Castle mountain backcountry. No recent avalanches have been observed in the forecast area.
Confidence
Intensity of incoming weather systems is uncertain on Saturday
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.
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.