Avalanche Forecast

Issued: Feb 24th, 2020 4:00PM

The alpine rating is moderate, the treeline rating is moderate, and the below treeline rating is moderate. Known problems include Storm Slabs.

Avalanche Canada shorton, Avalanche Canada

Email

Small storm slab avalanches are easy to trigger at all elevations, so be diligent with choosing low-consequence terrain and avoiding terrain traps.

Summary

Confidence

Moderate - Uncertainty is due to how the snowpack will react to the forecast weather.

Weather Forecast

MONDAY NIGHT: Partly cloudy, light wind from the west, alpine temperatures drop to -12 C.

TUESDAY: Increasing cloud with light flurries starting in the afternoon and up to 5 cm of snow, moderate southwest wind, alpine high temperature around -6 C.

WEDNESDAY: Cloudy with isolated flurries and trace accumulations of new snow, light to moderate southwest wind, alpine high temperature around -3 C with freezing level climbing to 1200 m.

THURSDAY: Cloudy with light flurries, moderate southwest wind, alpine high temperatures around -2 C with freezing level climbing to 1500 m.

Avalanche Summary

Over the weekend, thin soft slabs were reactive to skier traffic, especially on wind affected slopes. These slabs will become increasingly touchy as the new snow stacks up and settles into a cohesive slab.

Snowpack Summary

15-30 cm of recent snow has buried a widespread layer of surface hoar (size 5-15 mm). This layer exists on all aspects and elevations except for steep solar aspects where it was melted by sun and formed a crust. Surface hoar sitting on a thin sun crust may exist on lower angle solar aspects which is a particularly nasty combination. The new snow will likely become increasingly reactive to human triggers as it stacks up and settles into a cohesive slab. The mid and lower snowpack are generally well settled and strong.

Terrain and Travel

  • Choose slopes that are well supported and have limited consequence.
  • Carefully assess open slopes and convex rolls where buried surface hoar may be preserved.
  • Be aware of the potential for human triggerable storm slabs at lower elevations, even on small features.
  • Avoid terrain traps such as gullies and cliffs where the consequence of any avalanche could be serious.

Problems

Storm Slabs

An icon showing Storm Slabs

15-30 cm of recent snow is sitting on top of a widespread layer of surface hoar at all elevations. On solar aspects the surface hoar is sitting on a crust, a particularly nasty combination. 

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Feb 25th, 2020 4:00PM