The snowpack has gained some strength with the drop in temperatures and cloud cover but convective lift is making it difficult to forecast snowfall amounts on Sunday. Be on the lookout for dry loose avalanches in areas that receive more than 5 cm of snow as new snow will sit over a crust in most locations and be easy to trigger. This thinly buried, breakable crust is making skiing pretty awful in most locations but sheltered areas on true north aspects are still holding some good snow.
There is a cornucopia of weak interfaces throughout the snowpack depending on aspect, elevation, and local terrain influences. There have been a few avalanches this past week which appeared to have stepped down to multiple layers.
The bottom of the snow pack is inherently weak with well developed Facets and Depth Hoar. Persistent slab avalanches have stepped down to the deep persistent slab since the last storm meaning large triggers can influence this basal weakness.
No new activity was observed on the Icefields Parkway today thanks to cloud cover limiting solar effect.
Several wet loose avalanches were observed last week occurring mid to late afternoon at all elevations on southerly aspects. Many of these natural avalanches stepped down to the persistent slab with some triggering the deep persistent slab.
Cornice failures and loose wet avalanches are expected to start back up when the sunshine returns early next week. We may also see some dry loose activity in areas that receive more snow than forecast on Sunday.
Don't forget to post avalanche observations to the MIN.
1-3 cm of new snow (mostly graupel) sits over a breakable sun crust at all elevations on solar aspects. True north aspects are faceted with widespread wind effect in open areas at tree line and above. Approximately 20-50cm down is a persistent slab sitting over a facet layer in sheltered terrain or a weak crust at low elevations / southerly slopes. The lower snowpack is generally weak with large facets and depth hoar at the base.Snow depth varies from 60-150cm.
Sunday
Flurries.
Accumulation: 2-8 cm.
Alpine temperature: High -6 °C.
Ridge wind light to 15 km/h.
Freezing level: 1400m
Monday
Cloudy with sunny periods and isolated flurries.
Precipitation: Trace.
Alpine temperature: Low -15 °C, High -8 °C.
Ridge wind light to 15 km/h.
Freezing level at valley bottom.
Tuesday
Sunny with cloudy periods.
Precipitation: Nil.
Alpine temperature: Low -11 °C, High -4 °C.
Light ridge wind.
Freezing level: 1600 m
