Avalanche Forecast
Issued: Feb 14th, 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
Though it can be found extending into the alpine, surface hoar has been most reactive at the treeline elevation where conservative decision making is ESSENTIAL. Also watch for slow to bond wind slabs in strange places due to variable wind directions and cold temperatures.
Summary
Confidence
High -
Weather Forecast
SUNDAY NIGHT - Partly cloudy / trace of new snow possible / light south west wind with potential for some localized moderate wind / low near -19
MONDAY - Overcast / 1-5 cm / light westerly wind / high near -12
TUESDAY - Increasing cloud / light west wind / high near -12
WEDNESDAY - Afternoon clearing possible / light westerly wind / highs near -8
Avalanche Summary
On Sunday a ski cut triggered a size 1.5 on an open feature at the treeline/alpine interface in the Lizard Range. This failed on the late January persistent surface hoar layer.
Despite the the lack of snow, there has been in increase in activity on the persistent weak layer. On Thursday and Friday there were human and remote triggered avalanches up to size 2 reported. Locations like Mount Fernie, 2000, Liverwurst and McDermid were a few location examples. Some of the avalanches were remote triggered from a distance away. Some folks submitted MINs, you can read them here.
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
February has been a busy one for avalanche activity with human triggered avalanches going back well over a week that are too numerous to list. Do some research and check out the MIN reports in our region when planning your trip, 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 the surface hoar interface at treeline is the biggest repeat offender, and things have been most reactive 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.
- 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.
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
Problems
Persistent Slabs
Human triggering of this layer is likely. Small terrain features are producing small avalanche results, bigger features could produce larger more dangerous avalanches. 40-65 cm snow sits above a buried weak layer of surface hoar, facets, and a crust (depending on elevation and aspect). The surface hoar interface is the biggest repeat offender, and things have been most reactive on northerly and easterly aspects at treeline, but don't let your guard down elsewhere! These kinds of avalanches can happen in surprisingly mellow terrain and be triggered from a distance away.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Wind Slabs
Look out for wind slabs in unusual places. There have been some localized moderate to strong winds from variable directions. Newer reactive wind slabs will be slow to bond where they sit over cold sugary facets. There is also potential for wind slabs to step down to the late January persistent layer.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Feb 15th, 2021 4:00PM
