Avalanche Forecast
Issued: Feb 7th, 2020 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Deep Persistent Slabs.
mkoppang,
Avalanche Canada
5-8cm of recent snow has provided some opportunities for good skiing on the previous surfaces. Windslabs are you transition into steep treeline or alpine areas are still within the range of skier triggerability so be heads up the higher you get.
Summary
Confidence
High -
Weather Forecast
Up to 10cm of snow is forecast to fall overnight and through Saturday with moderate winds that are becoming more northerly by early morning on Saturday. Temperatures will be in the -6C range midday.Â
Avalanche Summary
Numerous loose dry slides out of extreme terrain up to sz 1. No recent slab activity was noted.Â
Snowpack Summary
Recent snow of up to 8cm is covering the Feb 5th Temperature crust up to 2000m. Very little wind affect was noted today but the recent snow is now burying the previous windslabs that are 10-50cm thick in alpine areas. The December 31st Surface hoar layer was found down 85cm at 2200m today and it was hard to trigger but sudden planar in nature (cash register drawer) when affected. The windslabs felt drummy in certain areas as you moved into treeline terrain which prompted forecasters to back off there original objective and seek out mellower terrain.Â
Terrain and Travel
- Approach steep open slopes at and below treeline cautiously, buried surface hoar may exist.
- Avoid slopes that sound hollow or drum-like.
- Be careful with wind slabs, especially in steep, unsupported and/or convex terrain features.
- In areas where deep persistent slabs may exist, avoid shallow or variable depth snowpacks and unsupported terrain features.
Problems
Wind Slabs
Wind slabs of varying density are everywhere at upper elevations and range in thickness from 10 to 50cm. Human triggering is most likely in steep, convex and/or unsupported terrain.
Aspects: North, North East, East, South East.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
This is the bottom 40cm of the snow pack (November crust/facet combo). There is potential for a surface wind slab to step down to this weak layer creating a very large slide. A recent full depth avalanche near lake louise reminds us that this layer is still active this season.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Feb 8th, 2020 4:00PM
