Avalanche Forecast

Issued: Jan 17th, 2019 3:00PM

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

Alberta Parks michael.olsthoorn, Alberta Parks

The bottom half of the snowpack is weak.  Careful route selection is advised.

Summary

Confidence

High -

Weather Forecast

Friday will bring mostly a cloudy day with light flurries, a temperature of -7c and strong SW winds.  The weather models are not all in agreement for Saturday; some are talking about 15cm of snow and others 5 cm.  One thing they agree on is that the winds for Saturday could be in the neighborhood of 70-100km/hr from the SW.

Avalanche Summary

No new avalanches were observed today.

Snowpack Summary

Large surface hoar was observed mostly in sheltered areas.  This will be on our radar when the next snow flies.  Widespread wind slabs are present in the alpine and down into the open areas of tree line.  The upper snow pack is dense and still producing sheers down about 40cm on the December 30 facet layer and down 70cm on the Dec 10 basal facet interface(bottom 55 cm of the snow pack) .  The eye opener is that the sheer with the basal facets is still clean and fast and the consequences of triggering this layer would mean that the entire snowpack could come down. 

Problems

Wind Slabs

An icon showing Wind Slabs
Expect to find wind slabs at all elevations. The depth and sensitivity to triggering are highly variable across the forecast region.
Avoid convexities or areas with a thin or variable snowpack.If triggered the storm/wind slabs may step down to deeper layers resulting in large avalanches.Be aware of thin areas that may propogate to deeper instabilites.

Aspects: North, North East, East, South East.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 2.5

Deep Persistent Slabs

An icon showing Deep Persistent Slabs
Any avalanche has the potential to trigger the basal facets, resulting in large avalanches.
Carefully evaluate and use caution around thin snowpack areas.Remote triggering is a concern, watch out for adjacent slopes.Be aware of the potential for full depth avalanches due to weak layers at the base of the snowpack.

Aspects: North, North East, East, South East, South, North West.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1.5 - 3

Valid until: Jan 18th, 2019 2:00PM