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

Feb 4th, 2016–Feb 5th, 2016

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

Regions

Jasper.

The best skiing will be found on sheltered tree-line slopes but remember that a touchy interface exists between the new snow slab and old facets.  There have been dramatic propagations and close calls in the past week.

Weather Forecast

Light snow through Friday with 10+ cm possible by Sunday.  Freezing levels forecasted between 1300 and 1600 m then cooling slightly on Sunday.  Wind will be a player with Moderate to Strong SW winds expected with the new snow on Saturday.

Snowpack Summary

Wind slab continues to form at tree-line and above on North-Easterly aspects below ridge crests and cross-loaded terrain. These slabs are loading a weak and facetted mid-pack that has a layer of concern down about 60cm at the interface between old facets and new snow. Isolated pockets of decomposing surface hoar at tree-line down 40cm.

Avalanche Summary

Lots of natural avalanche activity on Wednesday, mainly slab avalanches to size 2 on steep solar aspects between 1500 - 2500m, as well as numerous point releases to size 1.5, mainly on Westerly aspects.  No avalanche patrol on Thursday.

Confidence

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

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.

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.