Conditions are tricky. There is real potential to trigger surprisingly large avalanches. Traveling in avalanche terrain right now requires an advanced skill-set.
Confidence
Fair - Timing, track, or intensity of incoming weather is uncertain for the entire period
Weather Forecast
Monday: Cloudy with flurries turning to snow late in the day. Mild temperatures continuing, with the freezing level around 1500m. 8-15cm overnight. Strong south-westerly winds.Tuesday: Continuing snow and moderate south-westerly winds. A little bit cooler.Wednesday: Mainly cloudy with light flurries and possible sunny breaks. Light winds.
Avalanche Summary
A widespread natural avalanche cycle occurred up to size 3 in response to very warm temperatures and loading of start zones by strong winds on Friday and Saturday. Video footage here: https://bit.ly/yR4E8r . On Saturday, a snowmobiler was killed in a size 3 slab on a south-west aspect at treeline in the Corbin Creek area. Over the last week, there were several reports from in or near the region of near misses, including a snowmobiler who triggered an avalanche and was buried for around 30 minutes, remote-triggered avalanches, and slab avalanches running into unusually low-angled terrain.
Snowpack Summary
Recent storm snow has become moist on solar aspects, and on all aspects at low elevations. The mid February surface hoar layer is now down between 40 & 100cm and is more prevalent in the west and south of the region, particularly in the Flathead. Recent snowpack tests as well as a rider-triggered avalanche on this weak layer indicate that it still has the potential to be triggered in many areas and if it is triggered, a large avalanche could result. Remote-triggering, triggering from below and triggering on low-angled terrain are also concerns. Lingering concern remains for basal facets, particularly in shallower snowpack areas with steep, rocky start zones. Cornices have grown large and threaten slopes below.
Problems
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.
Storm Slabs
Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.
Persistent Slabs
Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.