Remain cautious of wind slabs in steep and immediate lee features. Be wary of large cornices.
A weak layer of surface hoar buried Jan 11 may be found 40-70 cm deep on open, sheltered slopes near and below treeline. Although likely unreactive to skiers, there is uncertainty as to the distribution and reactivity of this persistent slab problem across the region.
Monday night: Cloudy / south winds, 10 km/h / alpine low temperature -15
Tuesday: Cloudy with sunny breaks / southeast winds, 10-20 km/h / alpine high temperature -10
Wednesday: Cloudy with sunny breaks / east winds, 10 km/h / alpine high temperature -12
Thursday: Cloudy with sunny breaks / variable winds, 10 km/h / alpine high temperature -12
On Sunday in Glacier National Park, a skier triggered a size 2 avalanche upon entrance into a cross-loaded terrain feature. Other recent avalanche activity includes small size 1-1.5 wind slabs, a few large cornice failures, and loose dry sluffing in steep and southerly terrain.
We're continuing to track a layer of surface hoar from early January, the most recent activity reported on this layer was January 17 from Clemina Creek documenting cracking and propagation in sheltered treeline and below treeline areas on surface hoar buried 40-50 cm deep. Now trending unreactive, this is a layer we will continue to monitor.
A dusting of low density snow overlies a widespread layer of surface hoar up to 15 mm in areas. The snowpack boasts a variety of surfaces including scoured and pressed surfaces in exposed terrain, large cornices, isolated wind slabs, and variable wind affected and facetted snow in more sheltered terrain. Cold temperatures are encouraging surface faceting and breaking down wind slabs. A thin sun crust may be found on steep solar aspects. Below 1600 m, 20-30 cm of snow is settling above a decomposing melt freeze crust.
Observers continue to find a preserved layer of surface hoar down 40-70 cm in sheltered, open slopes at and below treeline. Recent snowpack tests have produced sudden results on this layer, other tests have found it unreactive, as such it continues to warrant slope-specific assessment.
Deeper in the snowpack, a couple of older persistent weak layers may still be identifiable from late and early December, consisting of surface hoar and a crust with faceted snow and buried anywhere from 100-200 cm deep. Prolonged periods of inactivity and unreactive snowpack test results suggest that these layers have trended towards dormancy.
