Avalanche Forecast

Issued: Jan 8th, 2014 8:19AM

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.

Avalanche Canada mbender, Avalanche Canada

Summary

Confidence

Poor - Timing, track, or intensity of incoming weather system is uncertain on Saturday

Weather Forecast

A westerly flow dominates the next 3 days. A number of weather systems are lined up to bring varying amounts of precipitation and wind to the interior regions.Thursday: Light snowfall, alpine temperatures -7, moderate west winds.Friday: Light snowfall, alpine temperatures -5, winds moderate west and southwestSaturday: Moderate to locally heavy snowfall, alpine temperatures -4, freezing level 1300m, winds moderate to strong west.

Avalanche Summary

There are no new reports of avalanche activity in the past 2 days. Although I would expect that with some new snow combined with moderate winds Wednesday into Thursday that we'll see thin wind slab releases to size 1 in the alpine.

Snowpack Summary

Up to 10 cm of new snow sits on a variety of snow surfaces ranging from older stiff wind slab, a soft layer of facetted snow and/or surface hoar. 50-80cm below the surface from you may find at various depths a thin melt freeze crust below 2100m and a couple of buried weak layers (surface hoar, facetted snow, and/or a crust) that continue to be reactive in snowpack tests.There are two deeper layers of note. The late-November persistent weak layer consists of a sun crust on steep south facing slopes and surface hoar in sheltered areas and is now buried 90-160cm below the surface. The October deep persistent weak layer consists of a layer of facets sitting on a crust at the base of the snowpack. This layer is predominantly found on northerly aspects at treeline and in the alpine. The depth of both these layers makes directly triggering an avalanche on them unlikely (maybe a heavy load on a thin spot in steep terrain). Their presence could, however, increase the size of a potential avalanche through step-down.

Problems

Wind Slabs

An icon showing Wind Slabs
New snow and moderate west winds have created windslabs in the lee of terrain features.
Be cautious as you transition into wind affected terrain.>

Aspects: North, North East, East.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Persistent Slabs

An icon showing Persistent Slabs
The presence of persistent weak layers increases the likelihood of larger avalanches that could release to a depth of a meter or even more.
Dig down to find and test weak layers before committing to a line.>Avoid areas with a thin or variable snowpack.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Unlikely - Possible

Expected Size

3 - 6

Valid until: Jan 9th, 2014 2:00PM