Avalanche Forecast
Issued: Apr 6th, 2023 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Persistent Slabs and Storm Slabs.
CB,
Avalanche Canada
Expect changing snow conditions and rising avalanche hazard as an incoming spring storm brings light to moderate snow with moderate SW winds.
If more snow falls then expected, hazard could rise to Considerable in the alpine by Friday afternoon.
Summary
Confidence
Avalanche Summary
Wed: skier triggered, sz 1, SE asp, alpine behind Mt Bonney. This was a thin slab abv a crevasse failing down ~15 cm.
Wed: natural aval sz 2.5, possible cornice fall off Mt Bonney, MIN.
Tues: Two moist snow skier triggered avals at the top of av crest. These were sz 1.5-2, triggered on a sun at the bottom of the recent storm snow down ~15cm.
Tues: cornice failure from above caught a person on Cheops N 1 , knocking them downslope ~300m.
Snowpack Summary
Expect a surface crust on solar aspects and dry snow on polar aspects. 15-20cm of settled snow is covering the March 31st which is a solid crust on solar aspects and isolated surface hoar/facets on polar aspects.
The mid and lower snowpack is generally strong. However, the basal weakness from November can still be found near the ground in many locations. This layer will remain a concern until the end of the season.
Weather Summary
Frontal system brings snow starting tonight with flurries continuing through Friday, next storm arriving Sunday.
Tonight: Cloudy scattered flurries, Alp low -3*C, mod S wind, FZL 1500m
Fri: Snow, 15-20 cm Alp high -1*C, light gusting to mod SW wind, 2000m FZL
Sat: Snow, 5cm, Alp high -3*C, mod SW wind, 1800m FZL
Terrain and Travel Advice
- Watch for fresh storm slabs building throughout the day.
- Be carefull with sluffing in steep terrain, especially above cliffs and terrain traps.
- Potential for wide propagation exists, fresh slabs may rest on surface hoar, facets and/or crust.
Problems
Persistent Slabs
Use caution on solar slopes where a sun crust in present down 10-35 cm. On polar aspects, this interface is spotty surface hoar and facets. The forecasted storm will load this weak layer and increase the likelihood of triggering and expected avalanche size.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Storm Slabs
An incoming storm will start to build a storm slab Friday. Moderate SW winds will deposit snow on lee slopes in exposed areas. Rain is possible below treeline, which will further destabilize the snowpack. Watch of signs of unstable snow such as cracking, whumpfing and recent avalanche activity.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Apr 7th, 2023 4:00PM
