Avalanche Forecast
Issued: Feb 11th, 2021 3:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Persistent Slabs and Wind Slabs.
jcoulter,
Avalanche Canada
That layer is still a player! Conservative trip plans are the best way to manage the combination of a persistent avalanche problem and extreme cold weather. Read more about these tricky moderate conditions in this forecaster blog.
Summary
Confidence
Moderate - Uncertainty is due to the fact that persistent slabs are particularly difficult to forecast.
Weather Forecast
THURSDAY NIGHT - Mostly clear / light to moderate north east wind / alpine low temperature near -28
FRIDAY - Cold, a few clouds / light north east wind / alpine high temperature near -18
SATURDAY - Increasing cloud / light to moderate north east wind / alpine high temperature near -20
SUNDAY - Overcast / light southerly wind/ highs near -15
Avalanche Summary
On Wednesday there was a size 1.5 skier triggered avalanche that failed on the late January surface hoar/facet layer. It was on a south east facing slope in the Tunnel Creek area. See MIN
On Tuesday there were a couple of smaller skier triggered avalanches, but of note was a remote triggered size 2 on Mt. Fernie (suspected surface hoar). Also on Tuesday, explosive control yielded wind slab avalanche results up to size 2.
February has been a busy one for avalanche activity with human triggered avalanches going back over a week that are too numerous to list. Do some research and check out the MIN reports in our region, click here.
Many thanks to the community for sharing information through the Mountain Information Network!
Snowpack Summary
Recent northerly and shifting winds have reverse loaded features; slabs may be found in open terrain on a variety of aspects. Surface faceting and surface hoar growth is occurring with clear nights and frigid temperatures.
A persistent weak layer lurks 30-70 cm below the surface. In some places it consists of surface hoar, in other places just facets, or crust/facet combinations. This weak interface has been responsible for the majority of recent avalanches. Reports suggest it is touchiest on northerly and easterly aspects, but don't let your guard down elsewhere.
Below 1600 m a hard melt-freeze crust is underneath 20-40 cm recent snow. A solid mid-pack sits above a deeply buried crust and facet layers near the bottom of the snowpack (150-200 cm deep), which is currently unreactive.Â
Terrain and Travel
- Carefully assess open slopes and convex rolls where buried surface hoar may be preserved.
- Be aware of highly variable recent wind loading patterns.
- Avoid terrain traps such as gullies and cliffs where the consequence of any avalanche could be serious.
- Watch for signs of instability like whumpfing, hollow sounds, shooting cracks or recent avalanches.
Problems
Persistent Slabs
This layer is STILL a player. Each day there is a steady trickle of rider triggered avalanches on this layer. Small terrain features are producing small avalanche results, bigger features could ruin your day. 40-65 cm snow sits above a buried weak layer of surface hoar, facets, and a crust (depending on elevation and aspect). Reports suggest it is touchiest on northerly and easterly aspects, but don't let your guard down elsewhere.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Wind Slabs
Variable winds may carry loose snow and build wind slabs in exposed and open features. Use caution around ridges, cornices, and loaded features. In steeper terrain, be cautious of dry-loose avalanches and mindful of sluffing.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Feb 12th, 2021 4:00PM
