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

Feb 8th, 2020–Feb 9th, 2020

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

Regions

Cariboos.

Wind slabs at upper elevations are the main concern. The forecast calls for a stable weather pattern in the next few days.

Confidence

High - Confidence is due to a stable weather pattern with little change expected.

Weather Forecast

Saturday Night: Cloudy with clear periods. Light northwest wind. Alpine high temperatures around -10.

Sunday: Mainly cloudy with sunny breaks and isolated flurries. Light to moderate west wind. Alpine high temperatures around -8.

Monday: A mix of sun and cloud. Light west winds. Alpine high temperatures around -6.

Tuesday: Scattered flurries. Light to moderate southwest winds. Alpine high temperatures around -5.

Avalanche Summary

Reports of new avalanche activity Wednesday through Friday were limited to small (size 1-1.5) skier or rider triggered wind slabs along steep ridgetop features.

Reports from Wednesday included three very large (size 3) persistent slab avalanches in the southeastern part of the region, not far from Allan Creek. These avalanches failed naturally on the 150 cm-deep late December surface hoar described in our snowpack summary. They occurred on north and east aspects at around 2300 metres.

Snowpack Summary

20-60 cm of snow from the last week overlies previously wind-affected snow at higher elevations, with diminished depths of about 20-30 cm above a widespread melt-freeze or rain crust up to about 1700 metres. This recent snow has shown variable reactivity, with reports showing a mix of soft wind slabs around treeline, sluffing of low density snow in steep terrain, and poor bonding with the buried crust where it exists.

The mid and lower snowpack are generally well settled, however an aging weak layer of surface hoar from late December, currently buried 70 to 150 cm deep, has shown surprisingly long-lived instability on slopes between 1700-2400 m (above the crust elevation and below the most wind-affected elevations), warranting increased caution around steeper slopes in this elevation band, particularly in the southern half of the region.

Terrain and Travel

  • Avoid freshly wind loaded features, especially near ridge crests, roll-overs and in steep terrain.
  • Use extra caution around cornices: they are large, fragile, and can trigger slabs on slopes below.
  • Be alert to conditions that change with elevation and sun exposure.

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.