Avalanche Forecast

Issued: Feb 11th, 2016 7:21AM

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

esharp, Avalanche Canada

Purcells.

It is still possible to trigger large avalanches. Hazard will fall as the temperature drops, but forecasting when and how this will happen is challenging. It would be prudent to keep things conservative until the snowpack cools off and settles.

Summary

Confidence

Moderate - Forecast snowfall amounts are uncertain on Sunday

Weather Forecast

FRIDAY: snow starting in the morning with accumulations of up to 5cm through the day. SATURDAY: 5-8cm snow overnight, flurries through the day. SUNDAY: Up to 10cm of snow. Winds will be light from the west through the forecast period. Freezing levels will hover at 1500m.

Avalanche Summary

A continued cycle of natural loose wet sluffs reaching Size 2 has been associated with daytime warming over the last couple of days. A naturalÂ Size 1.5 avalanche was observed in the Kicking Horse slackcountry on Thursday that apparently ran on a reloaded bed surface in a wind loaded feature.Â The interface is suspected to be the early January weak layer.Â Natural persistent slab avalanche activity was also observed earlier in the week, with a report of two Size 2.5s also in the Kicking Horse backcountry, that also released on the surface hoar, facet and crust weakness as deep as a meter down.

Snowpack Summary

Wet surface snow capped by a supportive melt freeze crust can be found on solar aspects and at lower elevations,Â Dry snow can still be found on high north facing terrain. New surface hoar growth may be found at and below treeline on shaded aspects. Sustained winds have scoured north and west-facing alpine slopes and formed fresh wind slabs and cornices. The early January surface hoar/ facet layer is typically down 70-90 cm. Recent very large avalanches have been failing on this interface in the north of the region (see avalanche discussion) and it continues to produce sudden planar results in snow pit tests. In general, the lower snowpack is well settled and strong, apart from some thin snowpack areas where basal facets exist.

Problems

Wind Slabs

Recently formed wind slabs remain sensitive to human triggers.

Be cautious as you transition into wind affected terrain.>Travel on ridges to avoid freshly wind loaded features. >

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 4

Persistent Slabs

A buried weak layer of surface hoar remains a concern, especially around Golden where it has recently created some very large avalanches.

Avoid convexities or areas with a thin or variable snowpack.>Avoid thin, rocky or sparsely-treed slopes.>Be cautious around open slopes and convex rolls at and below treeline where buried surface hoar may be preserved. Big alpine features are also suspect.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

3 - 5

Valid until: Feb 12th, 2016 2:00PM