Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches possible, human triggered probable.
Below Treeline
Natural avalanches possible, human triggered probable.
Alpine
Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches possible, human triggered probable.
Below Treeline
Natural avalanches possible, human triggered probable.
Alpine
Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches possible, human triggered probable.
Below Treeline
Natural avalanches unlikely, human triggered possible.
Regions
Glacier.
http://www.pc.gc.ca/apps/scond/Cond_E.asp?oID=15974&oPark=100205We still have a significant instability buried in the snowpack, so resist the temptation to jump onto the big lines. Lots of sun and rising freezing levels will stress the snowpack on solar aspects today.
Weather Forecast
We should see plenty of sunshine today with freezing levels rising as high as 1900m. Clouds will roll in tonight with a minor disturbance bringing trace amounts of snow tomorrow. The freezing levels will remain elevated until Friday, when we head back into the Arctic deep freeze with clear skies and cold temperatures.
Snowpack Summary
1-1.5m of storm snow is settling into a cohesive slab over the Jan 28/22 facet/surface hoar/crust interface. Snowpack tests suggests this weak layer is difficult to trigger, but if failed has high propagation propensity. Below this the snowpack is well settled. A surface sun crust has been found on steeper south and west aspects.
Avalanche Summary
Several size 2.5 avalanches were observed from southerly tree-line aspects yesterday. From Saturday a size 2.5 slab avalanche was observed around noon behind the Asulkan Hut. This could have been remotely triggered or triggered naturally, but is indicative of the lingering persistent weak layer buried a metre below the surface.
Confidence
Problems
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.
Cornices
Cornice Fall is the release of an overhanging mass of snow that forms as the wind moves snow over a sharp terrain feature, such as a ridge, and deposits snow on the downwind (leeward) side. Cornices range in size from small wind drifts of soft snow to large overhangs of hard snow that are 30 feet (10 meters) or taller. They can break off the terrain suddenly and pull back onto the ridge top and catch people by surprise even on the flat ground above the slope. Even small cornices can have enough mass to be destructive and deadly. Cornice Fall can entrain loose surface snow or trigger slab avalanches.
