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

Dec 6th, 2012–Dec 7th, 2012

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

South Rockies.

Confidence

Poor - Due to variable snowpack conditions

Weather Forecast

Overnight and Friday: Light snowfall / moderate northwest winds / Freezing level at surfaceSaturday: No precipitation / Light northwest winds / Freezing level at surfaceSunday: Light snowfall / Light southwest winds / Freezing level at surface

Avalanche Summary

No recent avalanche observations.

Snowpack Summary

Recent storm accumulations have been highly variable throughout the region; however, some ares saw moderate to heavy snowfall a few days ago. In general winds have been strong creating widespread windslabs at higher elevations. Warmer temperatures and rain at lower elevations have created moist surfaces that will most likely form a temperature crust with dropping freezing levels. Cornices are also reported to be unseasonably large and potentially unstable.There have been reports of buried surface hoar up to a metre down. This layer, which was buried about a week ago, seems most prevalent on the west side of the region. Little is known about its current reactivity.At the base of the snowpack you may find the early November crust which is associated with a layer of facets either directly above or below.In general, snowpack data is sparse in this region and significant variations likely exist from one drainage to another. Digging down and making your own observations will be critical to safe slope selection. Any observations from the field are welcome at [email protected].

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.