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, 2020–Jan 29th, 2020

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, human triggered possible.
Below Treeline
Natural avalanches unlikely.

Regions

South Rockies.

Lingering pockets of wind-drifted snow remain a concern for Wednesday at higher elevations. Seek out sheltered slopes and watch for reactive wind slabs around steep rolls and ridge features.

Confidence

High - Confidence is due to a stable weather pattern; little change is expected for several days.

Weather Forecast

Tuesday night: Clearing skies, isolated flurries, light west winds, alpine temperature -7 C, freezing level dropping to valley bottom.

Wednesday: Mix of sun and cloud, isolated flurries, moderate southwest winds with strong gusts, alpine high temperature -4 C, freezing level around 1500 m.

Thursday: Mix of sun and cloud, light southwest winds, alpine high temperature -1 C, freezing level around 1500 m.

Friday: Partly cloudy, isolated flurries, moderate southwest wind with strong gusts, alpine high temperature 2 C, freezing level rising to above 2000 m overnight.

Avalanche Summary

Several recent natural, small to large (size 1-2.5) wind slab avalanches were reported on northwest through northeast aspects at upper elevations.

On January 16th, a natural, size 2 wind slab stepped down to the deep persistent basal facets below a rock band, details here.

Snowpack Summary

Continuing west and southwest winds have formed stiff wind slabs on lee and cross-loaded terrain features at upper elevations. 

A crust can be found up to treeline and on solar aspects in the alpine due to previous warming and sun exposure. 

A well consolidated mid-pack overlies a generally weak basal snowpack. The bottom 10-20 cm of the snowpack consists of facets and deteriorating crusts. Although inherently weak, the benign weather pattern this week will likely promote a decreasing trend in reactivity for this avalanche problem. Areas that are most likely to harbor this problem are shallow, rocky start zones. 

Terrain and Travel

  • Watch for wind-loaded pockets especially around ridgecrest and in extreme terrain.
  • Avoid steep, rocky, and wind effected areas where triggering slabs is more likely.

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.