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 6th, 2023–Mar 7th, 2023

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

Regions

Northwest Inland, Kispiox, Microwave-Sinclair, Ningunsaw, South Bulkley, South Bulkley, Telkwa.

Wind slabs are aging but may still be triggerable. Spread your group out on large, connected pieces of slab-covered terrain in case of an unexpected surprise. Thin rocky areas remain a concern for triggering deeply buried weak layers.

Confidence

High

Avalanche Summary

No new avalanches were reported over the weekend and through Monday.

Prior to the weekend there were numerous reports of natural wind slab and cornice-triggered avalanches up to size 2.

Over a week ago, several large deep persistent slab avalanches were reported in the alpine, including a natural size 3 near Kispiox, a cornice-triggered size 2.5 at Hudson Bay and several explosive controlled size 2-3 near Ningunsaw.

Snowpack Summary

Firm, wind affected surface snow in exposed terrain features. Old wind slabs in cross loaded and lee features. Sun crusts on steep, solar aspects. Softer snow in very sheltered terrain features.

Several other crusts, layers of facets, or surface hoar can be found in the top 150 cm of the snowpack, but have not shown any significant avalanche activity or snowpack test results recently.

The lower snowpack consists of weak, basal facets which may become active with any rapid change or shock to the snowpack, such as heavy loading or dramatic warming.

Weather Summary

Monday night

Cold and clear as the outflow continues. Wind from the north at 20 km/h. Temperature -20˚C.

Tuesday

Cold and clear overnight clouds developing by the afternoon. 5 cm of new snow in the afternoon into the evening. Wind from the north 10km/h. Temperature rising to -5˚C by the afternoon.

Wednesday

Cloudy. 5 cm of new snow. Wind from the east at 10 km/h. Temperature from -10˚C to -5˚C.

Thursday

Clearing Wednesday night and clear through the day. Winds will be light and vary in direction. Temperature -17˚C in the morning warming to -5˚C by the afternoon.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Recent wind has varied in direction so watch for wind slabs on all aspects.
  • Conditions may have improved, but be mindful that deep instabilities are still present.
  • Avoid shallow, rocky areas where the snowpack transitions from thick to thin.
  • Pay attention to cornices and give them a wide berth when traveling on or below ridges.

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.

Deep Persistent Slabs

Deep Persistent Slab avalanches are the release of a thick cohesive layer of hard snow (a slab), when the bond breaks between the slab and an underlying persistent weak layer deep in the snowpack. The most common persistent weak layers involved in deep, persistent slabs are depth hoar or facets surrounding a deeply buried crust. Deep Persistent Slabs are typically hard to trigger, are very destructive and dangerous due to the large mass of snow involved, and can persist for months once developed. They are often triggered from areas where the snow is shallow and weak, and are particularly difficult to forecast for and manage.