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 12th, 2022–Feb 13th, 2022

Alpine
Natural avalanches unlikely.
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

North Rockies.

A widespread surface crust will create safe avalanche conditions but poor riding quality.

If this crust breaks down at lower elevations loose wet avalanches will be possible in steep terrain.

Confidence

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

Weather Forecast

The ridge of high pressure will start to break down with increasing cloud cover and the potential for light precipitation.

Saturday Overnight: Mainly cloudy with the potential for light precipitation. Freezing level dropping to around 500 m. Moderate northwest winds at ridgetop.

Sunday: Mainly cloudy with light precipitation. Freezing level rising to around 1500 m in the afternoon. Light southwest winds at ridgetop.

Monday: Cloudy with snowfall. Freezing level around 1000 m. Light to moderate southwest winds at ridgetop.

Tuesday: Mainly cloudy with light snowfall. Freezing level around 500 m. Strong to extreme northwest winds at ridgetop. 

Avalanche Summary

During the rain event on Wednesday, a natural avalanche cycle occurred. Numerous wet loose avalanches were observed on all aspects and elevations. A few notable large slab avalanches were observed in the south of the region, which we suspect occurred during this rain event. Examples of these avalanches can be seen in this MIN report. 

The last persistent avalanches associated with the late January surface hoar layer occurred on February 7th in the south of the region. These natural avalanches occurred on a shaded aspect below treeline.

Snowpack Summary

Recent rain and high freezing levels created a widespread curst on the snow surface of variable thickness that extends all the way to mountain top. Where this crust is thick and supportive, avalanches are unlikely. Warm temperatures, rain or strong solar radiation could cause this crust to break down.

Below the crust, last week's 30-50 cm of storm snow buried a weak layer of surface hoar crystals. The last reported avalanche on this layer was on February 7th in the southeast of the region and it is becoming increasingly hard to find in the snowpack with no recent reactivity in tests. 

The lower snowpack is generally strong and well-bonded. The base of the snowpack is expected to be weak and faceted in shallow, rocky slopes east of the divide.

Terrain and Travel

  • A crust on the surface will help bind the snow together, but may make for tough travel conditions.
  • When a thick, melt-freeze surface crust is present, avalanche activity is unlikely.
  • As surface loses cohesion due to melting, loose wet avalanches become common in steeper terrain.
  • Watch for areas of hard wind slab on alpine features.

Problems

Loose Wet

Loose Wet avalanches are the release of wet unconsolidated snow or slush. These avalanches typically occur within layers of wet snow near the surface of the snowpack, but they may quickly gouge into lower snowpack layers. Like Loose Dry Avalanches, they start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-wet avalanches include point-release avalanches or sluffs. Loose Wet avalanches can trigger slab avalanches that break into deeper snow layers.

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.