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 27th, 2022–Dec 28th, 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 unlikely, human triggered possible.
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

Northwest Coastal, Kitimat, Nass, Rupert, Seven Sisters, Shames, Stewart, Howson, Microwave-Sinclair, Telkwa.

Continually assess the bond between the recent snow and the faceted surface below. Wind and storm slabs likely won't bond well meaning that they will remain reactive to rider traffic.

Confidence

Moderate

Avalanche Summary

Over the past few days natural storm slab avalanches up to size 2.5 have been observed in the region. These storm slabs are generally failing on the layer of facets and surface hoar created during the cold snap.

Snowpack Summary

New wind slabs exist in exposed terrain at treeline and above with the largest being on west aspects. A new crust could be found on the surface at lower elevation terrain an on some sun exposed slopes.

Around 50cm of recent storm snow overlies a variety of surfaces formed during the previous cold snap. In the alpine these surfaces are generally facets, old wind slab and Surface hoar. At treeline it is more likely to find surface hoar at this interface in sheltered terrain.

A layer of surface hoar and facets from early December can be found down 50cm in shallower snowpacks and over 80cm in deeper areas. recently this layer has not been reactive but still produces sudden results in snowpack tests.

The mid November crust is buried down over a meter in most places and is unreactive. The mid and lower snowpack is generally well settled.

Weather Summary

Tuesday Night

Light flurries bringing trace amounts of new snow. Light southwest winds and a low of -6 at 1500m.

Wednesday

Mainly cloudy with light flurries bringing trace amounts of new snow. Light variable winds and a high of -5 at 1500m.

Thursday

Cloudy with light flurries bringing 5 to 10cm of new snow. Light northeast winds and a high of -6 at 1500m.

Friday

Cloudy with flurries bringing around 5cm of new snow. Light southwest winds and a high of -6 at 1500m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Continue to make conservative terrain choices while the storm snow settles and stabilizes.
  • Storm slabs in motion may step down to deeper layers resulting in large avalanches.

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.