Avalanche Forecast
Regions: Purcells.
Confidence
Fair - Due to variable snopack conditions
Weather Forecast
Mostly clear and dry for the forecast period. Although warmer on Thursday and Friday, freezing levels are expected to remain in or near valley bottoms. Winds are expected to be light but gusty northwesterlies.
Avalanche Summary
A skier was killed in a Size 3 avalanche in the Dogtooth range near Golden on Friday. The 4th skier on the slope triggered the slide. On Saturday a skier triggered another Size 3 persistent slab avalanche in the Quartz Creek alpine, the crown averaged 100cm in depth & the avalanche was reported to have run full path. The group had been skiing in the area all day without result until the avalanche happened. Avalanche activity on Sunday was confined to operational explosive use & produced avalanches to Size 2 on high elevation NE facing slopes.
Snowpack Summary
Warm temperatures and light to moderate precipitation settled the 40-60cm of recent storm snow and created upside down slabs and/or thin surface crust on Monday. Since then, light amounts dry snow is maintaining the snow supply for wind slab development, but cold temperatures are likely starting to improve storm slab stability. Touchy mid-December surface hoar and basal facets remain a persistent problem. Recent snowpack tests produced easy results that show a high propensity to propagate fractures. When combined with weak wind slabs, thin trigger points, other weaknesses within and under the recent storm snow, the result is a highly variable snowpack with the potential for deep slab avalanches, especially from heavy, thin spot, and/or step-down triggers.
Avalanche Problems
Wind Slabs
Aspects: North, North East, East, South East, South, South West.
Elevations: Alpine, Treeline.
Likelihood: Possible - Likely
Expected Size: 2 - 5
Persistent Slabs
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Possible
Expected Size: 3 - 7
Deep Persistent Slabs
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Unlikely - Possible
Expected Size: 4 - 7