With continued reports of remote and rider trigged avalanches on the persistent weak layer, conservative decision making and careful route finding are ESSENTIAL. This layer has been most reactive at the treeline elevation, but don’t let your guard down elsewhere.
Though most winds have been light, there have been some localized moderate to strong winds from variable directions (will likely switch to southerly Sunday) . 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.
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.
SATURDAY NIGHT - A few clouds / moderate easterly wind / low -22
SUNDAY - Partly cloudy / trace of new snow possible / light south west wind/ highs near -15
MONDAY - Overcast / trace of new snow possible / light west wind / high near -12
TUESDAY - Increasing cloud / light west wind / high near -12
There were reports of small natural avalanches in north facing fan features on Saturday.
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 triggered avalanches up to size 2 reported in the Lizard Range on the late January surface hoar layer. One was triggered remotely from 50 m away.
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!
Recent northerly and shifting winds have reverse loaded features; slabs may be found in open terrain on a variety of aspects. Winds are forecast to shift back to south west tomorrow. 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.
