Natural avalanches unlikely, human triggered possible.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely.
Alpine
Natural avalanches unlikely, human triggered possible.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely.
Alpine
Natural avalanches unlikely, human triggered possible.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely.
Regions
Purcells.
Wind slabs may be more susceptible to human triggers where they sit above a buried weak layer. Field observations are limited, so it is critical to supplement this forecast with your own observations.
Confidence
Moderate - Due to the number of field observations
Weather Forecast
MONDAY NIGHT - Cloudy with clear periods / light northwest winds / alpine temperatures near -12TUESDAY - A mix of sun and cloud / light west to northwest winds / alpine temperatures near -10WEDNESDAY - A mix of sun and cloud / light northerly winds / alpine high temperatures near -10, low temperatures near -15THURSDAY - Sunny with cloudy periods / alpine high temperatures near -6, low temperatures near -10
Avalanche Summary
No new avalanches have been reported in the region, however field observations are very limited. If you have been in the backcountry, please submit your observations to the Mountain Information Network.
Snowpack Summary
The early season snowpack is highly variable in the Purcells. Approximately 20 cm of snow fell last week which may have been blown into wind slabs on exposed northerly and northeasterly slopes. There are two layers of surface hoar (weak feathery crystals) being reported in the top 35-40cm. The surface hoar is most prominent at treeline, but it may be found in sheltered alpine areas. Both of these layers may be associated with a sun crust on south aspects in some areas.In shallow snowpack areas, the bottom half of the snowpack is reportedly weak and "hollow" feeling on shady aspects due to sugary, faceted snow.A prominent feature of the snowpack is a combination of a crust and faceted (sugary) snow found at or near the base of the snowpack.
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.