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 16th, 2017–Jan 17th, 2017

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

Regions

Little Yoho.

Incoming snow amounts are uncertain and are likely to vary across the forecast region. What is certain is that this new snow will land on a weak and suspect snowpack.

Weather Forecast

A large low pressure system is sitting off of the coast and is spinning precipitation towards the forecast region. As much as 35cmis predicted by Thursday in some models favoring the northern part of the region. Other models show very little. In either case expect temperatures to remain mild and winds to remain moderate to strong out of the SW.

Snowpack Summary

Wind slabs at treeline and above have formed over the past week first from North and followed by West winds. These hard slabs can be found in many start zone and open areas overlying a weak, faceted snowpack. In sheltered areas, and at lower elevations, surface snow remains weak and faceted providing poor support for travelers.

Avalanche Summary

A skier accidental sz 1 was reported near treeline on Helen Shoulder Sunday. A skier accidental size 1.5 by Panorama Meadows (Taylor Lake area) was reported Saturday. Both of these events sound as though they released on the deep persistent layer involving slabs over the facets. Numerus loose dry avalanches were observed Sunday at lower elevations.

Confidence

Timing, track, or intensity of incoming weather system is uncertain on Tuesday

Problems

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.

Loose Dry

Loose Dry avalanches are the release of dry unconsolidated snow and typically occur within layers of soft snow near the surface of the snowpack. These avalanches start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-dry avalanches include point-release avalanches or sluffs.