Avalanche Forecast

Good - -1

Thursday: Dry and clear, with freezing levels near valley bottoms and moderate northwesterly winds. Friday: Increasing cloud in the afternoon with freezing levels briefly rising as high as 1500m. Saturday: Light snowfall with freezing levels around 900m.

Recent observations include a slope-cut Size 1.5 20-40cm thick slab avalanche that ran on the mid-December persistent weakness where it was found to be facets on a very steep shallow rocky unsupported roll. Other reports include a few small natural avalanches from recent wind loading in cross-loaded treeline features, and skiers hucking pillows and cliffs on open slopes below treeline were triggering small 20-30cm thick soft slabs suspected to involve surface hoar buried early January. Finally, low density surface snow is sluffing readily in steep terrain.

Warm temperatures and light precipitation settled the 20-40cm 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, cold temperatures are likely starting to improve storm slab stability, and surface hoar is growing. A thin melt/freeze crust can be found in the upper snowpack as high as 1900m, and some areas are reporting surface hoar buried early-January now down 10-30cm. The late-December interface is now down 30-60cm and producing moderate to hard resistant snowpack test results. While the mid-December surface hoar/facet persistent weakness, down 40-100cm, is producing anywhere from easy to hard results, but consistently shows a high propensity to propagate fractures. Recent whumpfing suggests basal facets remain concern in shallow snowpack areas especially with heavy triggers in thin spots, and weaknesses in the slab above create the potential for step-down avalanches.