http://www.pc.gc.ca/apps/scond/Cond_E.asp?oID=15693&oPark=100205Warm temperatures and sunshine this weekend will cause natural avalanches, especially on south-facing aspects.
Weather Forecast
A strong inversion is setting up in the area, where valley bottoms will likely be near freezing, but alpine temperatures could rise to +5*C. These warm temperatures, coupled with strong sunshine, will pack quite a punch in destabilizing the snowpack on solar aspects. Light westerly winds are expected over the weekend.
Snowpack Summary
Over a meter of new snow from the last week is settling. It sits on a surface hoar/graupel layer. Strong SW winds have formed slabs in exposed areas at all elevations. Rain below 1300m formed a crust. The mid pack is well settled with the Nov28 surface hoar layer down around 2m where present. The facetted base is showing signs of strengthening.
Avalanche Summary
No new avalanches observed yesterday. Click on https://www.facebook.com/ParksMountainSafety to see images of the latest avalanche cycle this past Monday.
Confidence
Timing or intensity of solar radiation is uncertain
Problems
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.
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.