Avalanche Forecast

Issued: Mar 17th, 2020 4:00PM

The alpine rating is moderate, the treeline rating is low, and the below treeline rating is low. Known problems include Wind Slabs and Loose Wet.

Avalanche Canada shorton, Avalanche Canada

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Watch for unstable snow on sun-exposed slopes and steep wind-affected terrain.

Summary

Confidence

High - We have a good understanding of the snowpack structure and confidence in the weather forecast

Weather Forecast

A high pressure system brings clear dry conditions for the week.

TUESDAY NIGHT: Clear skies, light northeast wind, freezing level drops to valley bottom, alpine temperatures drop to -10 C.

WEDNESDAY: Clear skies, light north wind, freezing level climbing to 1500 m, alpine high temperatures around -2 C.

THURSDAY: Sunny with a few clouds, light south wind, freezing level climbing to 1500 m, alpine high temperatures around -2 C.

FRIDAY: Sunny, light south wind, freezing level climbing to 1500 m, alpine high temperatures around -2 C.

Avalanche Summary

On Monday warm sunny weather resulted in several wet loose avalanches on south-facing slopes in steep rocky terrain (see this MIN report for an example). Over the weekend a few size 1 human triggered wind slab avalanches were reported, and one size 2 wind slab was triggered by riders on a southwest aspect near Mt. Currie.

Looking forward, daily warming will likely cause more wet loose avalanches and potentially weaken cornices and lingering wind slabs.

Snowpack Summary

A surface crust now exists in all terrain except shaded alpine slopes. Open terrain is heavily wind affected. The snowpack is generally strong and settled, however weak faceted snow and crusts exist near the base of the snowpack in some areas, particularly the eastern and northern parts of the region. This layer is considered dormant, as it hasn't produced an avalanche since Feb 20.

Terrain and Travel

  • Back off slopes as the surface becomes moist or wet with rising temperatures.
  • Carefully evaluate steep lines for wind slabs.

Problems

Wind Slabs

An icon showing Wind Slabs

Triggering wind slab avalanches remains possible after strong northeast wind formed slabs in atypical terrain features.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Loose Wet

An icon showing Loose Wet

Sunny weather will cause wet loose avalanches on steep sun-exposed slopes. It could also weaken cornices.

Aspects: East, South East, South, South West, West.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 1.5

Valid until: Mar 18th, 2020 4:00PM