Avalanche Forecast
Issued: Mar 2nd, 2018 4:00PM
The alpine rating is Persistent Slabs and Wind Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeA weak and variable snowpack from recent strong winds and cold temps warrants a cautious approach. Identify features of concern.
Summary
Weather Forecast
Sunday will be cloudy with sun and flurries, trace snow, -20 to -13 and NE light winds. Monday will be a mix of sun and cloud, no snow, -19 to -14, and light Westerly wind. Tuesday will be sun and cloud, -16 to -11, and light SW winds. Wednesday will be cloudy and flurries, a trace of snow, -15 to -8, with light SW winds.
Snowpack Summary
Wind slabs and extensive wind effect is found in open areas. Recent warm temps and solar effect will have created a crust on solar aspects below treeline. The upper snowpack is a 50 to 80 cm thick slab that sits on three weak layers in the mid-pack. The entire snowpack is faceted after two weeks of cold, dry weather.
Avalanche Summary
Friday's road patrol to Sunwapta noted one giant cornice failure, the size of a bus, with no initiation below. No other naturals were noted in this immediate area. On Wednesday, isolated large Na avalanches were observed. One windslab from a cross loaded pocket on a W aspect and one persistent slab on an E aspect.
Confidence
Problems
Persistent Slabs
A slab up to 80cm thick overlies: weak faceted crystals (well developed in shallow areas), surface hoar (at, and just above treeline), and sun crusts ( on steep S and W aspects). Faceting has reduced slab strength below treeline and in shallow areas.
Be wary of slopes that did not previously avalanche.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Wind Slabs
Previous wind effect will be difficult to assess under new snow. Expect hardslabs in the alpine and at treeline. The cold has reduced the tension in these but caution is still warranted.
Best conditions on sheltered northerly aspects.If triggered the wind slabs may step down to deeper facet layers resulting in larger avalanches.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Mar 3rd, 2018 4:00PM