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

Nov 25th, 2014–Nov 26th, 2014

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

Regions

South Rockies.

The avalanche danger is expected to increase as weather systems roll across the provinceadding to the developing storm slab. In deeper snowpack areas Wednesday's avalanche danger may be HIGH.

Confidence

Poor - Due to the number of field observations

Weather Forecast

A low pressure system off the coast will move inland bringing significant precipitation across the south of the province on Wednesday and Thursday. Uncertainty lies in precipitation amounts and the timing of rising freezing levels; however, some models indicate freezing levels reaching 2000m by late Wednesday. On Friday a northwest flow will bring cooling, light flurries and a mix of sun and cloud.Wednesday: 10-20 cm of snow / Moderate to strong west winds / Freezing levels at about 1500mThursday: 10-20cm of snow / Strong southwest winds / Freezing levels at about 2000mFriday: Mix of sun and cloud with light flurries / Light northwest wind / Freezing level at surface

Avalanche Summary

No avalanche activity has been reported. This may speak more to a lack of observations rather than actual conditions. In the neighboring Lizard/Flathead region, natural and human-triggered avalanches to size 2 have failed on basal facets. I suspect a similar pattern of avalanche activity may be developing in some of the deeper snowpack areas within this region. With forecast weather, I expect continued storm slab activity with the potential to trigger deeper, more destructive weaknesses at the base of the snowpack.

Snowpack Summary

As we begin our forecasting season we are working with very limited field data. If you have been out in the mountains, please send us a note with your observations to [email protected] limited field data that we have received suggests that there is not enough snow below treeline for avalanche activity. At higher elevations, the developing storm slab may be sitting on a weak layer of facetted snow, surface hoar, and/or a wind or sun crust that developed earlier in the month. This storm slab has been touchy to human triggers and has been reactive on basal facets in the Lizard/Flathead Region. I would expect similar conditions in some of the deeper snowpack areas within the South Rockies region.I expect avalanche activity to increase in size and frequency with forecast wind, snow and warming.

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.