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 29th, 2017–Jan 1st, 2018

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

Regions

Waterton Lakes.

Fresh, deep powder disguises a thin snowpack.  Be aware that where wind affect is obvious, danger may be higher than forecast ratings.  Rising temperatures and sun on cold loose snow may keep danger levels elevated heading into Monday.

Weather Forecast

Another large snowfall Friday night may double current storm snow totals.  Moderate NE winds possible for a short time overnight. Otherwise light winds are forecast; but pay attention as as any wind will up the danger.  Clearing trend on Sunday. Temperatures will remain in the -20's overnight and through Saturday, then rise to around -5 by Monday.

Snowpack Summary

35cm low density new snow (and increasing), with soft Storm Slabs lee to NE winds in highly exposed areas. Down 70cm is a layer of facets over a crust. This has been giving moderate and hard, sudden results in tests in Western areas. It seems most sensitive 1600-1900m, however these elevations are mainly below threshold snow depths for avalanches.

Avalanche Summary

Poor visibility limited observations on Thursday and Friday. Several small natural avalanches (loose dry and wind slab) were observed on NW-NE aspects on Wednesday, in steep terrain at and below Treeline. Widespread whumping and shooting cracks were noted from 1700-1900m, but all except lee areas had too many protruding stumps/rocks to avalanche.

Confidence

Forecast snowfall amounts are uncertain on Saturday

Problems

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.

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.