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

Dec 31st, 2019–Jan 1st, 2020

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

Regions

Northwest Inland.

Current snowpack and weather conditions are highly variable throughout the region. Dangerous avalanche conditions exist where new snow accumulations or wind loading exceeds depths of 25 cm.

Confidence

Low - Uncertainties in both the snowpack structure and the weather forecast limit our confidence.

Weather Forecast

Tuesday night: Scattered flurries accumulating to 5 cm overnight, moderate wind from the southwest, alpine temperatures around -3 C freezing level around 1000 m.

Wednesday: Snow with accumulations of 5-15 cm, strong wind from the west, alpine temperatures drop from -2 to -12 C through the day, freezing level drop to valley bottom.

Thursday: Mix of sun and cloud with isolated flurries, moderate wind, alpine high temperatures around -10 C.

Friday: 5-10 cm of snow, moderate wind, alpine high temperatures around -8 C.

Avalanche Summary

Stormy weather is likely forming unstable storm slabs and wind slabs, as well as adding stress to buried surface hoar layers. There are reports of recent large natural avalanches in the Telkwa Range (size 2-3), mostly on northeast aspects. Some were likely triggered by cornices, while many appear to have run on the buried surface hoar layers. A size 1.5 skier-triggered avalanche was reported in the Ashman area on Friday. The avalanche occurred on a convex north-facing slope at treeline and also failed on a surface hoar layer 50 cm below the surface (see full report and photos in this MIN post).

Snowpack Summary

Recent snowfall amounts as well as forecast snowfall amounts vary widely for Wednesday, but there are likely storm slabs developing in parts of the region. Reports suggest there are two layers of surface hoar buried 25-50 cm below the surface. A skier triggered avalanche at Ashman and snowpack test results near Smithers suggest these layers have now become reactive. There is uncertainty about the distribution of this layer, but the sheltered slopes around treeline elevations are the most suspect for having preserved surface hoar.

Terrain and Travel

  • Storm snow and wind is forming touchy slabs. Use caution in lee areas in the alpine and treeline.
  • Dial back your terrain choices if you are seeing more than 25cm of new snow.
  • Carefully assess open slopes and convex rolls where buried surface hoar may be preserved.
  • Watch for signs of instability like whumpfing, hollow sounds, shooting cracks or recent avalanches.

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.

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.