Avalanche Forecast
Issued: Apr 7th, 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.
KR,
Avalanche Canada
High uncertainty in the ever-changing weather forecast!
Be prepared to change your plans over the next few days and keep a vigilant eye for changing conditions in the field.
Summary
Confidence
Avalanche Summary
Small loose moist snowballing on all aspects treeline and below today.
Yesterday (Thursday) a group boot-packing on Grizzly Mountain triggered a size 2.0 windslab in a variable snowpack depth area.
On Wednesday, a skier triggered, size 1 on a SE aspect in the alpine behind Mt Bonney. This was a thin slab (~15cm) above a crevasse. A natural cornice fall avalanche sz 2.5 also occurred off Mt Bonney, MIN.
Snowpack Summary
Expect a breakable 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. Be ready for this layer to wake-up in the next few days.
Weather Summary
An upper trough brings flurries tonight, with an Atmospheric River poised to arrive Sunday and stall over the Interior Monday.
Tonight: Flurries 11cm. Alpine low -6°C. Moderate SW wind. FZL 1300m
Sat: Flurries 6cm, Alp high -4°C, mod gusting strong SW wind. FZL 1800m
Sun: Snow 19cm. Alp Low -5 °C, High -2 °C. Mod gusting strong SW wind, FZL 1900m
Terrain and Travel Advice
- Look for signs of instability: whumphing, hollow sounds, shooting cracks, and recent avalanches.
- Potential for wide propagation exists, fresh slabs may rest on surface hoar, facets and/or crust.
- Be carefull with sluffing in steep terrain, especially above cliffs and terrain traps.
Problems
Persistent Slabs
Use caution on solar slopes where a sun crust is present down 10-30 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 overnight tonight. Moderate SW winds will deposit snow on lee slopes in exposed areas. Rain is possible below treeline, which will further destabilize the snowpack.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Apr 8th, 2023 4:00PM
