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

Mar 26th, 2013–Mar 27th, 2013

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

Regions

Cariboos.

Confidence

Good

Weather Forecast

The ridge of High pressure is expected to continue to influence the interior ranges for the next few days. As the ridge weakens we may see high cloud reducing the exposure to strong solar radiation. Nights are expected to continue to be clear and cool. Freezing levels in the North should rise during the day to about 1800m, and to about 2000m in the South.

Avalanche Summary

Natural wet-loose avalanches up to Size 2 continue to be reported from throughout the region. This avalanche activity as well as natural cornice failure is expected to continue with warm and sunny weather throughout the forecast period.

Snowpack Summary

Surface faceting and surface hoar growth has been prevalent on shady slopes and at upper elevations, while the surface snow on sun-exposed slopes and at lower elevations has been subject to daily melt-freeze cycles. Cornices are reported to be very large and weakly bonded. Wind slabs are reported to be strengthening, but may continue to be sensitive to human-triggers. The weak layer of buried surface hoar from March 10th is down more than a metre in most places, and is giving variable results in snow profile tests. However, this deep persistent weakness remains a concern because of the potential for very large avalanches particularly with heavy triggers such as cornice falls or lighter triggers in thin snowpack areas.

Problems

Cornices

Cornice Fall is the release of an overhanging mass of snow that forms as the wind moves snow over a sharp terrain feature, such as a ridge, and deposits snow on the downwind (leeward) side. Cornices range in size from small wind drifts of soft snow to large overhangs of hard snow that are 30 feet (10 meters) or taller. They can break off the terrain suddenly and pull back onto the ridge top and catch people by surprise even on the flat ground above the slope. Even small cornices can have enough mass to be destructive and deadly. Cornice Fall can entrain loose surface snow or trigger slab avalanches.

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.

Persistent Slabs

Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.