Avalanche Forecast

Issued: Apr 7th, 2023 4:00PM

The alpine rating is considerable, the treeline rating is moderate, and the below treeline rating is moderate. Known problems include Persistent Slabs and Storm Slabs.

KR, Avalanche Canada

Glacier.

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

Low

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 -6Â°C. Moderate SW wind. FZL 1300m

Sat: Flurries 6cm, Alp high -4Â°C, mod gusting strong SW wind. FZL 1800m

Sun: Snow 19cm. Alp Low -5 Â°C, High -2 Â°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

Likely

Expected Size

1 - 2.5

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

Likely

Expected Size

1 - 2.5

Valid until: Apr 8th, 2023 4:00PM