Avalanche Forecast

Issued: Mar 11th, 2017 3:10PM

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

Alberta Parks matt.mueller, Alberta Parks

Wind, new snow and warm temps have created new windslabs in the last 24 hours.

Summary

Confidence

High -

Weather Forecast

The strong westerly winds will continue overnight. Alpine temps will fall to the -7 range. Tomorrow will have isolated flurries with no significant accumulation. The winds will be 30-40km/hr from the west. While not part of our forecast, its worth mentioning the solar radiation is noticeable these days. Expect clear skies or thin cloud to have an impact on southerly exposures.

Avalanche Summary

Nothing from the last 24hrs.

Snowpack Summary

Moderate to strong SW winds have contributed to new, alpine windslabs on N-S aspects. Fortunately these are easy to spot and predict in terms of location. In terms of "triggerability", it felt as though these could be easily triggered in steep, convex terrain. Treeline also had these slabs, however they were limited to wind exposed areas. For the deeper layers, the situation is still the same as it has been. To make a long story short, the deeper layers are widespread and very difficult, if not impossible to trust. Below treeline the warm temps made for moist, sticky snow that will form a thin crust overnight.

Problems

Wind Slabs

An icon showing Wind Slabs
There are multiple layers of slabs out there. It's hard to identify just one as a problem. Recognize that it is possible for a small surface slab to start a chain reaction that could go all the way to the bottom of the snowpack.
Minimize exposure to overhead hazard from cornices.Caution in lee and cross-loaded terrain near ridge crests.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Deep Persistent Slabs

An icon showing Deep Persistent Slabs
Similar to the windslab problem, these deeper layers consist of many weak layers being lumped together into a single problem. The take home point is the fact that they are near the bottom of the snowpack and any avalanche involving them will be big!
Be aware of the potential for wide propagations.Avoid exposure to overhead avalanche terrain, large avalanches may reach the end of run out zones.Pay attention to overhead hazards like cornices which could easily trigger the deep persistent slab.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Unlikely - Possible

Expected Size

2 - 4

Valid until: Mar 12th, 2017 3:00PM