http://www.pc.gc.ca/apps/scond/Cond_E.asp?oID=23025&oPark=100244Human triggered avalanches are possible and have the potential to be large and destructive. Be cautious of thin snowpack areas and limit your exposure to large slopes. With warm afternoons its best to get an early start and end early.
Weather Forecast
Friday and Saturday will have 1600m freezing level with -10 Celsius overnight. Saturday will be variable cloud with periods of sun. Light westerly winds through weekend. Sunday-Monday will have increased clouds and 2-4cm of snow, perhaps higher amounts in Marmot basin area. Sunday night may have less of a freeze.
Snowpack Summary
Moist surface snow in the afternoons and isothermal conditions in shallow spots BTL on solar aspects. Overnight -10 Celsius helping with morning freeze. There is significant variation in snowpack depth through-out the area with a large proportion being shallow. The persistent slab down 30-70cms has been most active in the area around the ski hill.
Avalanche Summary
Thursday's field team in the Icefields area report only minor pin-wheels and snow-balling on immediate solar aspects. No field patrol Friday.
Confidence
Timing or intensity of solar radiation is uncertain on Saturday
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.
Loose Wet
Loose Wet avalanches are the release of wet unconsolidated snow or slush. These avalanches typically occur within layers of wet snow near the surface of the snowpack, but they may quickly gouge into lower snowpack layers. Like Loose Dry Avalanches, they start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-wet avalanches include point-release avalanches or sluffs. Loose Wet avalanches can trigger slab avalanches that break into deeper snow layers.
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.