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 28th, 2022–Jan 29th, 2022

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

Regions

North Rockies.

Avalanche danger will increase as new snow and wind form fresh and reactive wind slabs in lee terrain features at upper elevations.

Confidence

Moderate - Uncertainty is due to the limited number of field observations.

Weather Forecast

Friday night: Flurries starting, bringing up to 5 cm. Strong southwest wind. Freezing level valley bottom.

Saturday: Snowfall 5-10 cm. Strong SW wind. Treeline high around -3 °C.

Sunday: Snowfall 5-15 cm. Moderate to strong SW wind. Treeline high around -2 °C. Freezing level 1000 m.

Monday: Snowfall 5-10 cm. Moderate NW wind. Treeline high around -8 °C. Freezing level valley bottom.

Avalanche Summary

No new reports of avalanche activity. 

Earlier in the week, several reports from the south of the region indicated wind slabs were reactive naturally and to explosives, size 2-3. Some of these were failing down to the bedrock in extreme terrain features. 

Snowpack Summary

The snow surface is highly wind affected in exposed terrain and wind slabs are lingering in leeward features. On steep solar aspects and at lower elevations, a melt-freeze crust may be found on the surface. In sheltered areas at treeline and below, a layer of small surface hoar crystals has been reported in the south of the region. 

A thin crust may be found under the last week's snow down 20-30 cm, which was the main sliding surface for the wind slab cycle last weekend. Another crust is found down around 70 cm but has not shown recent reactivity. The lower snowpack is generally strong and bonded, with one or multiple crusts near the ground. We suspect the lower snowpack could be weak in shallow, rocky, wind-affected slopes east of the divide.

Terrain and Travel

  • Fresh wind slabs will likely form throughout the day, diligently watch for changing conditions.
  • Wind slabs are most reactive during their formation.
  • Watch for avalanche hazard to increase throughout the day.
  • Seek out sheltered terrain where new snow hasn't been wind-affected.

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.