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

Jan 7th, 2023–Jan 8th, 2023

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

Sea To Sky, Brandywine, Garibaldi, Homathko, Powell River, Spearhead, Tantalus, Sasquatch, Sky Pilot.

Watch for changing conditions throughout the day; slabs may become increasingly reactive.

The timing of the next storm is uncertain, but hazard will increase as the storm pushes in.

Confidence

Moderate

Avalanche Summary

Some small (size 1) human-triggered wind slabs avalanches were reported around Whistler on cross-loaded slopes on Friday. One of them has failed on a buried surface hoar layer underneath the recent snow. Avalanche control triggered several size 1-5 to 2 storm slabs on steep alpine lee features around Blackcomb/Whistler. A natural avalanche cycle up to size 2 has taken place Thursday night/Friday morning. These avalanches occurred on lee aspects at treeline and above.

Snowpack Summary

Up to 15 cm of new snow has fallen into the region since Friday. Ongoing southerly and northerly winds have affected the storm snow in any open terrain and near ridgelines. On sheltered slopes, up to 45 cm of powder storm snow can be found. Snow is heavy and moist at lower elevations.

In sheltered terrain at treeline, a weak layer of surface hoar is buried under the storm snow down 20 to 45 cm. A thick crust formed in late December is down 40 to 70 cm. At lower elevations, this crust is up to 15 cm thick. In the alpine, it is thin and breakable.

Near the base of the snowpack, a weak facet/crust layer from mid-November can be found and is still a concern. In general, the snowpack is weak, faceted, and shallow.

Weather Summary

A weak trough will continue to push moisture in the region Saturday night with a southerly flow aloft. On Sunday, another trough will generate periods of light snow until Monday night. Overcast skies and dry conditions are expected Tuesday.

Saturday night

Snow 5-10 cm, southeast winds easing gusting 45 km/h, freezing levels around 1500 m, low of -2C at treeline.

Sunday

Snow 5-10 cm expected in the afternoon, another 10-15 cm overnight, moderate southerly winds gusting 50 km/h, freezing levels around 1500 m; high of -2C at treeline.

Monday

Cloudy with flurries up to 5 cm, moderate southerly winds gusting 50 km/h, freezing levels around 1200 m, high of -3C at treeline.

Tuesday

Cloudy; lingering flurries, light southeasterly winds, freezing levels around 1000 m, high of -4C at treeline.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Fresh wind slabs will likely form throughout the day, diligently watch for changing conditions.
  • Recent wind has varied in direction so watch for wind slabs on all aspects.
  • Avoid steep, rocky, and wind effected areas where triggering slabs is more likely.
  • Seek out sheltered terrain where new snow hasn't been wind-affected.
  • Conditions may have improved, but be mindful that deep instabilities are still present.

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.