Purcells

Natural avalanche activity has tapered off, but skier triggered avalanches are possible. Solar aspects seem to be most reactive with large avalanches failing on an old crust. Evaluate terrain carefully and conservative decision making is recommended.

Good

Tonight and Wednesday: A low pressure system moves inland to the South of the border. Light-moderate precipitation will begin this evening over the Southern ranges. Ridgetop winds light from the South. Alpine temperatures near -6 and freezing levels 1300 m. Thursday: Mainly cool and dry with some clouds. Ridgetop winds light from the West. Alpine temperatures near -7 and freezing levels at 1200 m. Friday: The ridge will remain over the region with dry, sunny conditions. Ridgetop winds will blow light from the West. Alpine temperatures near -9 and freezing levels at 1400 m.

On Monday, one size 2 natural slab avalanche occurred from an East aspect. Many operators in the region did control work using explosives and triggered slab avalanches size 1-3.5 on all aspects generally above 2200 m. The large avalanches that initiated from Southerly aspects ran on a buried crust interface down 80-100 cm.

Up to 80 cm of snow fell over the past week. The new snow added to ongoing storm snow instabilities, particularly on the west side of the region where accumulations have been highest. Buried beneath (60-100 cm) exists a surface hoar and a sun crust layer, which continue to be lingering concerns. Large looming cornices exist on ridgelines. Cornice fall could trigger a large slab avalanche on the slope below.Below treeline exists a melt-freeze crust with moist snow beneath it. The crust may be bridging instabilities deeper in the snowpack. If temperatures warm at lower elevations, you'll notice the crust breaking down and the snowpack becoming weaker.