Avalanche Forecast
Issued: Feb 1st, 2023 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Deep Persistent Slabs, Persistent Slabs and Wind Slabs.
llarson,
Avalanche Canada
Continue to exercise patience with this snowpack and avoid aggressive terrain choices.
Summary
Confidence
Moderate
Avalanche Summary
Small wind slabs continue to be triggered both naturally and with explosive control work, most of these occurrences were in the western part of our region.
Over the weekend a very large natural size 4 deep persistent slab avalanche was reported. This avalanche started as a wind slab in steep rocky terrain and stepped down to the ground.
Snowpack Summary
Wind slabs up to 20 cm in depth can be found on a variety of surfaces including previously wind-affected snow, a small layer of surface hoar, and a sun crust.
Our mid-pack has two layers that remain of concern. The first is down 20 to 40 cm and is a layer of surface hoar from early January. The second, is a layer of surface hoar, facets, and crust down 40 to 60 cm.
A layer from late November is down 70 to 130 cm and is part of a generally weak faceted snowpack. Snowpack depths range between 80 and 180 cm at treeline and are shallowest in the eastern part of our region.
Weather Summary
Wednesday Night
Partly cloudy, flurries 2 to 3 cm of new snow, winds 15 to 20 km/h westerly, treeline temperatures of -8 °C.
Thursday
Mostly clear skies, trace accumulations in the morning, 15 to 20 km/h southwest winds. Treeline temperatures -4 °C.
FridayIncreasing clouds, 2 to 5 cm of new snow starting later in the day, 10 to 20 km/h southwest winds, treeline temperatures -5 °C.
SaturdayMostly cloudy, 2 to 5 cm new snow, 15 to 20 km/h southwest winds, treeline temperatures -2 °C.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Avoid thin areas like rock outcroppings where you're most likely to trigger avalanches failing on deep weak layers.
- Uncertainty is best managed through conservative terrain choices at this time.
- Approach lee and cross-loaded slopes with caution.
Problems
Deep Persistent Slabs
A weak layer near the base of the snowpack, buried in November, continues to be reactive. Human and natural triggering of this layer remain possible, especially in shallow areas with variable snow depths. Avoid thin and rocky start zones and select routes that avoid exposure to large avalanche paths.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
Several weak layers sit in the upper and mid snowpack at prime depths for human triggering. Avoid convex rolls in sheltered terrain where buried surface hoar may be present. Stay disciplined and choose well supported, low consequence lines.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Wind Slabs
Wind slabs can be found at all elevations in open terrain features and range from soft to hard slabs depending on exposure to recent winds.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Feb 2nd, 2023 4:00PM
