Avalanche Forecast

Saturday night: Mostly cloudy, scattered flurries with trace accumulations, light to moderate southwest winds, freezing level dropping to 500 m.

Sunday: Mostly cloudy, up to 5 cm of snow, moderate southwest winds, freezing level rising to 1100 m and dropping to valley bottom.

Monday: Partly cloudy, light southeast winds, freezing level near 1200 m.

Tuesday: Mix of sun and cloud, light southwest winds, freezing level near 1300 m.

In the north of the region, reports indicated that an avalanche cycle occurred during the storm on Friday, where large (size 2.5) avalanches released naturally on a variety of aspects and elevations. 

There are still concerns about the reactivity of persistent weak layers in these areas. Over the past week, observers near Duffey Lake reported a large (size 2.5) avalanche on a north aspect at 1750 m that was thought to have released 1 m deep on a persistent weak layer. Last Sunday, a size 1.5 skier accidental was reported on a northwest aspect in the alpine, also near Duffey Lake. The slab is thought to have failed on a thin layer of facets, sandwiched between two wind-stiffened layers. 

In the south of the region, there have been numerous reports of large (size 2-3) natural glide slab avalanches over the past week. Glide slabs are most likely in areas of smooth ground cover such as rock slabs and can be large, involving the full depth of the snowpack. Carefully consider your access/egress routes where they cross under large paths. 

In the north of the region, another possible 5 cm of snow will add to the 20-30 cm that accumulated Friday. The recent snow has been accompanied by strong south winds, forming touchier slabs on leeward slopes. Pay attention to how wind has redistributed snow and investigate the bond of the new and old snow interfaces as you travel in the backcountry on Sunday. Massive cornices exist on ridgelines, which can act as triggers on slopes below.  

The load from new snow and wind has the potential to wake up buried weak layers. A layer of facets from mid-February has shown reactivity on north aspects near treeline and is primarily a concern where it separates wind-stiffened snow above and below. A deeper persistent weak layer buried in late January composed of a crust, facets or surface hoar also has the potential to re-awaken with large triggers, such as an avalanche in motion, cornice fall, or intense loading from snow/ wind. The lower snowpack is well settled and strong in most areas.

In the south of the region, danger ratings are Moderate, Low, Low due to a gradual cooling trend in the aftermath of a significant warm-up and with only trace accumulations of new snow. The snowpack is generally well consolidated with no concerns of buried weak layers but notable glide avalanche activity.

• Stay off recently wind loaded slopes until they have had a chance to stabilize.
• Avoid freshly wind loaded features, especially near ridge crests, roll-overs and in steep terrain.
• If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
• Cornice failure may trigger large avalanches.