Warming temperatures have settled the recent storm snow into a cohesive slab sitting on weak facets (sugary snow) that is ripe for human triggers; intense solar radiation will increase the likelihood of human triggered avalanches.
Summary
Confidence
Moderate -
Weather Forecast
FRIDAY NIGHT: Partly cloudy / Light, westerly winds / Alpine low -10 / Freezing level below valley bottom.SATURDAY: Partly cloudy in morning becoming mostly sunny / Light, westerly winds / Alpine high 2 / Freezing level rising to 1800 m.SUNDAY: Sunny / Light, northwesterly winds / Alpine high 5 / Freezing level rising to 2200 m.MONDAY: Sunny / Light, northwesterly winds / Alpine high 7 / Freezing level rapidly rising to 2500 m.
Avalanche Summary
On Thursday, several rider triggered persistent slab avalanches up to size 2 were reported on a variety of aspects at treeline elevations. Human triggering of these persistent slabs is expected to increase with the forecast sunshine and warming.On Wednesday, numerous naturally triggered wind slab avalanches up to size 2.5 and a few human triggered wind slabs up to size 1.5, were reported primarily on easterly aspects at treeline and above.
Snowpack Summary
15-30 cm of recent storm snow is sitting on a pile of facets (sugary snow), as well as a crust on sun exposed slopes. The recent storm snow has settled into a cohesive slab and is ripe for human triggering. This persistent slab is currently our primary concern.At lower elevations, a weak layer of surface hoar (weak, feathery crystals) buried in mid-January can be found approximately 50-90 cm deep. This layer has recently been unreactive, however, the forecast warming event may awaken this layer in low elevation areas such as steep cutblocks and large open glades.The base of the snowpack is composed of facets (weak, sugary snow) that sit on a crust. Large avalanches failing on these facets may become more likely after a long period of warming.
jsmith,
Avalanche Canada
