Stability has improved but there are still avalanche problems out there. If you see anything interesting, please submit an observation using our new website tool. For more details see: http://goo.gl/Tj0xPC
Weather Forecast
High pressure persists over the interior for the forecast period. A weak disturbance will result in increased cloud cover for Tuesday. Treeline temperatures will be around -6 and alpine winds should remain light. The south of the region may see light scattered flurries but less than 1 cm is expected. Wednesday and Thursday should see a mix of sun and cloud, treeline temperatures around -5, and light alpine winds.
Avalanche Summary
No new avalanches were reported at publish time on Monday. On Sunday, explosive control produced avalanches to size 2.5. These occurred on N-SE aspects between 2200 and 2500m elevation. Slab depth varied from 30 to 90cm. On Saturday, isolated natural activity was reported up to size 2.5 above 2400m.
Snowpack Summary
A surface crust exists to around 2100m and is generally supportive to skiers. Above this elevation is dry storm snow which is settling out and faceting. A new layer of surface hoar is currently forming on the snow surface. In exposed alpine terrain, strong southerly winds last week may have resulted in variable distribution of the surface snow and the formation of wind slabs. A thick rain crust with facets from early November is buried over 1 m down. Snowpack tests on this deep weak layers are showing improving results, but in some locations these layers are still reactive and has the potential to release large slab avalanches.
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.
Persistent Slabs
Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.