Avalanche Forecast

Poor - Due to limited field observations

A frontal system moves across the region Thursday night extending through mid day Friday bringing light to moderate precipitation and freezing levels near the surface. Winds will be building out of the west, expect values from 50 - 70 km/h in the alpine for the second half of the day. Temperatures will be near seasonal norms with a high of -6 and an overnight low of -12.

Observations from the Microwave area (S. of Dennis Lake) on Dec. 26: Several easily triggered soft slabs on steep features up to treeline. No alpine observations due to cranking winds and blowing snow. I would expect some natural avalanche activity at higher elevations, primarily in wind loaded terrain.

Strong winds have been the biggest story recently. Exposed windward slopes have been scoured and wind slabs have formed in lee terrain and may be susceptible to human triggering. There is now around 55-70cms of snow sitting on a surface hoar/crust/facet combo which is the result of the early December dry spell. This crust is widespread and exists in most start zones up to 2000m. Facets can reportedly be found above or below the crust. Prior to being buried, the surface hoar was destroyed by high winds in the alpine, but still coexists with the crust at treeline and below. What is the tipping point of this weak interface? In areas where this interface has reached its threshold, natural and human triggered avalanches up to size 2.5 have occurred. If they have yet to happen, I suspect they are gaining some strength but would still react to a rider trigger, especially in steeper, unsupported terrain features. In short, the upper snowpack is variable and deserves caution. It will also see increased load with forecast wind and snow. Beneath this the midpack is well settled and strong.