Storm slabs may be easy to trigger, particularly where they overly a weak layer. Best to keep things simple and avoid consequential terrain.
Storm slabs continue to be reactive to natural and human triggers, including being triggered remotely. They are particularly touchy where they overly weak surface hoar as well as in lee terrain features.
We've received many reports of widely propagating natural and human-triggered avalanches over the past few days, including remote triggers. They were mostly 50 cm deep and found at all elevation bands, failing on the buried surface hoar described in the Snowpack Summary.
Human-triggered avalanches remain likely as stormy conditions continue to form slabs and load the buried weak layer.
Around 50 cm of snow accumulated since Friday and another 10 to 20 cm is expected by Wednesday afternoon. The snow is falling with strong southwest wind, forming deeper deposits in leeward terrain features.
Around 50 to 80 cm deep, a preserved layer of surface hoar may be found in openings around treeline. The distribution of this layer appears to be widespread south of Highway 16 and spottier north of the highway. Where it exists, the layer has the likelihood of forming widely-propagating avalanches that can be remotely triggered. Beneath this layer, a hard melt-freeze crust from mid-November may be found.
Snow depths at treeline average 100 to 150 cm and decrease rapidly at lower elevations.
Tuesday Night
Cloudy. 5 to 15 cm of snow. 30 km/h southwest ridgetop wind. Treeline temperature -6 °C.
Wednesday
Cloudy. 5 cm of snow. 30 km/h southwest ridgetop wind. Treeline temperature -3 °C. Freezing level rising to 1500 m.
Thursday
Cloudy. 5 to 10 cm of snow. 30 km/h west ridgetop wind. Treeline temperature -6 °C.
Friday
Cloudy. 2 to 5 cm of snow. 30 km/h west ridgetop wind. Treeline temperature -9 °C.
More details can be found in the Mountain Weather Forecast.
