Confidence
Fair - Intensity of incoming weather is uncertainfor the entire period
Weather Forecast
Sunday: 7cm of new snow - moderate southwest winds - alpine temperatures of -8.0Monday: 8cm of new snow - moderate southwest winds - alpine temperatures of -9.0Tuesday: 20cm of new snow - moderate southwesterly winds - alpine temperatures of -7.0
Avalanche Summary
No new avalanche activity reported in the last 24 hours. Fresh wind slabs and cornices are sensitive to human-triggers and will continue to be with forecast weather.
Snowpack Summary
Dribs and drabs of new snow with moderate winds have been the norm over the last week. Wind-exposed slopes are predominately scoured and pressed, with pockets of wind slab from 10 to 35cm deep on North to East aspects at treeline and in the alpine. This recent snow overlies a weak rain crust that formed last weekend. This crust extends to treeline elevations and overlies buried surface hoar and/or facets 10cm below. Generally speaking, confidence in this interface is growing, especially since it has'nt seen a significant load at the elevations where it exists. In the alpine where the crust does not exist, a stiffer wind slab may over-ride surface facets that formed during the early December dry spell. A compression test on thursday showed easy, sudden results 35cm below the surface at 2250m on a North aspect.The mid and lower snowpack are generally well-settled and strong. Snowpack depths at treeline sit at about 130 throughout the region.
Problems
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.