Avalanche Forecast

Issued: Jan 30th, 2017 5:32PM

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

Avalanche Canada mbender, Avalanche Canada

Be aware of the potential for smaller avalanches to step down to deeper persistent weaknesses. A cautious approach to terrain selection is recommended.

Summary

Confidence

Moderate -

Weather Forecast

TUESDAY: Mix of sun and cloud, wind light northeast, alpine temperature -8WEDNESDAY: Mix of sun and cloud, wind light east, alpine temperatures -7THURSDAY: Mix of sun and cloud, wind light northeast, alpine temperature -8 More details can be found on theMountain Weather Forecast.

Avalanche Summary

Over the weekend alpine and tree line features were observed running to Size 3.5. Below tree line both storm and glide slab avalanche activity to Size 2 was observed. Numerous loose wet avalanches have also been reported at highway elevations over the past three days. Several avalanches involving the full depth of snowpack to size 3.5 were reported in the Ningunsaw and Bell 2 areas. One was reported a being remotely triggered by a skier from a distance of 150m away.

Snowpack Summary

A storm that impacted the region over Friday to Sunday morning delivered approximately 60-110 cm of new snow to the mountains, with the greatest depths accumulating in coastal areas. Strong to extreme southwesterly winds accompanied the storm while lower elevations saw precipitation falling as rain. It can be expected that 70-130 cm have accumulated above above the latest buried surface hoar layer from January 23rd. This surface hoar was previously reported growing up to size 10mm at tree line and below. It may be sitting on a crust below 1100m. Although storm slab activity has captured our attention, there continue to be several other surface hoar layers of concern from early January and Christmas. Some reports have shown these persistent weak layers to be rounding and bonding, however recent reports have shown hard sudden results in snowpack tests.

Problems

Storm Slabs

An icon showing Storm Slabs
recent snow and wind has created storm and wind slabs
The new snow will require several days to settle and stabilize.If triggered the storm/wind slabs may step down to deeper layers resulting in large avalanches.Be cautious as you transition into wind affected terrain.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

2 - 4

Persistent Slabs

An icon showing Persistent Slabs
The load on some of the persistent weaknesses buried in the snowpack has reached a critical level in some areas of the region
Be aware of the potential for wide propagations due to the presence of buried surface hoar layers.Avoid areas with overhead hazard.Be aware of thin areas that may propogate to deeper instabilites.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

3 - 4

Valid until: Jan 31st, 2017 2:00PM