Dashboard Regions Weather Stations Radar Alerts Glossary
Contact About
Log In

Register for an account and never miss a forecast again!

Register

Avalanche Forecast

Archived

Mar 1st, 2022–Mar 2nd, 2022

Alpine
Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches possible, human triggered probable.
Below Treeline
Natural avalanches unlikely, human triggered possible.
Alpine
Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely.
Alpine
Natural avalanches unlikely, human triggered possible.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely.

Regions

South Columbia.

Conservative terrain selection is recommended as the storm snow needs more time to strengthen and there is uncertainty about buried weak layers in parts of the region.

Confidence

Moderate - Uncertainty is due to how quickly the snowpack will recover and gain strength.

Weather Forecast

TUESDAY NIGHT: Cloudy with isolated flurries bringing trace amounts of snow, moderate wind from the southwest, treeline temperatures drop to -6 C.

WEDNESDAY: Mostly cloudy skies with some convective flurries bringing trace amounts of snow, light wind from the south with moderate gusts during flurries, treeline temperatures reach -2 C with freezing level reaching 1700 m.

THURSDAY: Cloudy with scattered flurries bringing 5 to 10 cm of snow, light wind from the northwest, treeline temperatures around -5 C.

FRIDAY: Mostly sunny, light wind from the northeast, treeline temperatures around -5 C.

Avalanche Summary

Storm slabs were reactive on Monday and preliminary reports from Tuesday suggest they were even more reactive. Reports from Monday included numerous small (size 1-1.5) human triggered avalanches at treeline elevations, but also a few larger (size 2) slabs on larger features. The avalanches were typically 20 to 40 cm thick, and many ran on recently buried crust and surface hoar layers.

Over the past week there have been regular reports of sporadic large (size 2 and 3) persistent slab avalanches in the Valhalla, Goat, and Kokanee Ranges. These avalanches occurred on 50 to 100 cm deep surface hoar and crust layers. While many of the reports have been on north and east facing slopes, they have occurred on all aspects. The weak layers associated with these avalanches are currently being stressed by warming and the weight of the new snow.

Snowpack Summary

Recent storm snow has likely settled into 20 to 35 cm of heavy powder at upper elevations and wet/crusty snow below 2000 m. Reactive slabs are likely found on wind loaded slopes and perhaps some isolated areas where this snow sits above sun crusts or feathery surface hoar. 

Two potential weak layers exist within the upper snowpack: the mid-February layer (down 40 to 60 cm) and the late-January layer (down 100 cm). They both consist of surface hoar and/or melt-freeze crusts. Recent trends suggest these layers have been most reactive in southern parts of the region around the Valhallas, Kokanee, and Goat Ranges. See photos of these layers from our forecasters' MIN report.

Terrain and Travel

  • Choose slopes that are well supported and have limited consequence.
  • Avoid freshly wind loaded terrain features.
  • Caution around convexities or sharp changes in terrain.
  • Approach steep, open and/or sparsely treed slopes cautiously.

Problems

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.