Purcells

Although the frequency of natural avalanches has gone down recently, the possibility of triggering a large, destructive avalanche is still very real. See the Forecasters Blog for more insight into this tricky situation.

Fair - Intensity of incoming weather systems is uncertain

The current ridge of high pressure will break down allowing for a series of pacific frontal systems to bring snowfall to the region for the forecast period.Sunday: Overcast skies and light snowfall / Light southerly winds / Freezing level at surfaceMonday: Light snowfall / Moderate to strong southwest winds / Freezing level at 900mSunday: Light snowfall / Moderate southwest winds / Freezing level at 1200m

In the north of the region on Friday, skiers initiated a cornice fall which triggered a size 2.5 slab avalanche on the slope below. The avalanche occurred on a north aspect and failed on a facet-surface hoar interface.

Snow surfaces include well-settled powder, surface hoar in sheltered areas and a thin sun crust on solar aspects. Recent variable winds have also created wind pressing in exposed terrain, and thin wind slabs may be found in some alpine features.The big news remains a mix of weak surfaces which were buried between the end of January and the beginning of February. This persistent interface lies between 50 and 120cm below the surface, and includes surface hoar, well developed facets and a mix of hard surfaces which remain widespread at all aspects and elevations. Although avalanche activity has tapered-off at this interface, destructive avalanches are still a very real concern with ongoing reports of human triggering and sudden snowpack test results. This low probability/high consequence scenario is tricky to manage as the warning signs may not be obvious. It's all about terrain choice. Put the odds in your favour by avoiding steep, unsupported slopes, areas with a thin or variable snowpack, or terrain with a significant overhead hazard.The mid and lower snowpack are strong and well consolidated. Weak basal facets exist in many areas, but triggering has now become unlikely.