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 15th, 2012–Dec 16th, 2012

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

Regions

Northwest Coastal.

Weather Forecast

Synopsis: The next Low pressure system is tracking south of the region so the NW is setting up for little precipitation, light wind, and continuted cool temperatures over the next few days.Sunday: Light to moderate SW wind with light & localized convective snow squalls and alpine temperatures around -8C and below freezing temperatures right to the valley.Monday & Tuesday: Light SW or W wind, light & localized snow flurries, continued cool temperatures with below zero at all elevations.

Avalanche Summary

Near Stewart only small loose slides from sttep cliffy terrain; otherwise no new naturals reported. Near the Shames backcountry evidence of a mid-week natural cycle of small (size 1 to 1.5) slabs was reported. No new recent reports from Terrace were received.

Snowpack Summary

The storm forecast for today (Saturday) didn't seem to make it onshore with any great punch, only light accumulations reported away from the coast. The upper snowpack should be mostly slowly settling powder with pockets of windslab or wind affected snow in exposed areas. Below this, near Shames at least, there may be some patchy surface hoar. Deeper in the snowpack professionals continue to monitor a crust down near the ground. It seems this problem is confined to  alpine areas and likely needs a large trigger and / or a shallow snow pack feature to trigger.

Problems

Storm Slabs

Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-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.