Avalanche Forecast

Issued: Feb 28th, 2017 3:22PM

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

Avalanche Canada istorm, Avalanche Canada

Forecast snow, wind, and warming will increase the size and likelihood of triggering avalanches.

Summary

Confidence

Moderate - Forecast snowfall amounts are uncertain

Weather Forecast

WEDNESDAY:  Another 5 to 10 cm new snow by Wed evening with moderate to strong SW or W winds. Temperatures warming with freezing level rising to around 1300m. THURSDAY: Yet another 5 to 10 cm by Thursday evening with SW winds. Continued warm with freezing level steady around 1300m FRIDAY:  Still snowing with 5 to 20cm forecast by Friday evening with strong SW winds. Continued warm with freezing level unchanged (around 1300m).

Avalanche Summary

Explosive control at treeline and alpine elevations released storm slabs 30 to 60 cm deep on Monday. Loose dry sluffing up to size 1.5 from steep terrain at all elevations was also reported. Slab avalanche size and likelihood is expected to increase with forecast new snow, wind, and warming.

Snowpack Summary

Storm snow accumulations of 30 to 50 cm from the past few days are reported through the region with deepest amounts in eastern areas. Wind slabs have formed in exposed areas from shifting SW to NW winds. More snow and wind is forecast. Recent snow rests on a sun crust on steep sun-exposed slopes and large surface hoar shaded aspects. Below that are a variety crusts and thin surface hoar layers, depending on aspect and elevation, with the primary mid-pack feature being the mid-February surface hoar/sun crust down 75-100 cm. Areas with a shallow snowpack (less than around 170 cm) generally have a weak snowpack structure with a deep persistent weakness of facets near the ground.

Problems

Storm Slabs

An icon showing Storm Slabs
New snow will become more reactive as warming temperatures and wind promote slab development. Shifting S to W winds may see touchy wind slabs form behind ridges and ribs, but also in open treeline areas.
Avoid freshly wind loaded features.Be cautious as you transition into wind affected terrain.Minimize overhead exposure during periods of heavy loading from new snow, wind.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Valid until: Mar 1st, 2017 2:00PM