A field team yesterday encountered slab conditions that were very touchy at treeline. More wind and new snow overnight will cause these conditions to continue today. Watch out for windslabs. The hazard will rise again on the weekend with warming.
Weather Forecast
Light to moderate snowfall today brings 5-10cm today, then tapers off on friday as a ridge builds bringing warm temperatures for the weekend and a rising freezing line. This freezing line will rise to 1300m on Friday and up to 2000m on Saturday.
Snowpack Summary
Up to 70cm of low density new snow and strong winds in the last 24hrs. Winds slabs have formed. Overnight 11cm with 14.3mm at Fidelity. The Nov 6 crust is down 200cm.
Avalanche Summary
25 new avalanches recorded along the highway from early on the 30th.
Confidence
Timing, track, or intensity of incoming weather system is uncertain
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.
Storm Slabs
Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-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.
Loose Dry
Loose Dry avalanches are the release of dry unconsolidated snow and typically occur within layers of soft snow near the surface of the snowpack. These avalanches start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-dry avalanches include point-release avalanches or sluffs.