Cautious decisions are key particularly on large terrain features or those around terrain traps. Forecasters do not have much confidence in the snowpack as whumphing continues. Evaluate snow and terrain carefully.
Weather Forecast
Expect -12 to -18 degrees Celsius and light winds for Tuesday. Winds will pick up Westerly with a little bit of snowfall starting Tuesday night extending into Thursday. Temperatures will be warming slightly.
Snowpack Summary
A persistent slab at TL and ALP is buried by 5-10cm of snow and light winds making for powdery conditions. A rain crust is buried by this recent snow below 1900m. A somewhat dense upper snowpack overlies a weak faceted base making for unpredictably dangerous avalanche conditions. A surface hoar layer may be 40cm deep yet remains unconfirmed.
Avalanche Summary
No patrol on Sunday or Monday. Nothing new noted on Saturday. Friday's patrol observed 2 avalanches remotely triggered by skiers size 1.5-2 in Columbia Icefield area at 2000m treeline elevation. Two size 2-2.5 noted in the alpine south of Parkers ridge. One was a cross-loaded NW alpine feature, the other was triggered by cornice failure.
Confidence
The weather pattern is stable
Problems
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.
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.