Avalanche Forecast

Issued: Mar 13th, 2024 4:00PM

The alpine rating is high, the treeline rating is high, and the below treeline rating is considerable. Known problems include Persistent Slabs, Wind Slabs and Loose Wet.

Avalanche Canada swerner, Avalanche Canada

Email

UPDATE THURSDAY AT 7:40 AM

Avoid avalanche terrain. Warm temperatures, sun, and a weak snowpack have created very dangerous avalanche conditions.

Summary

Confidence

Moderate

Avalanche Summary

Monday and Tuesday saw a widespread avalanche cycle up to size 3.5. Numerous natural persistent slab avalanches were reported on all aspects, failing on the early February rain crust with very wide propagation.

Ongoing natural, rider and remotely triggered avalanches persist on this layer.

Snowpack Summary

Recent storm snow totals near 40 to 80 cm across the region with the Cariboo's and eastern ranges near Valemount seeing the higher amounts. The new snow sits on sun crusts and wind-affected snow from previous strong southwest winds. A melt-freeze surface crust exists up to 1900 m.

Two layers of surface hoar and sun crust can be found in the top meter of the snowpack. One from late February and the other from early March.

A thick and hard widespread crust that formed in early February is buried about 70 to 120 cm deep. This crust has a layer of facets above it in many areas.

The snowpack below this crust is generally not concerning except in shallow alpine terrain.

Weather Summary

Wednesday Night

Mix of cloud and clear. 10 to 20 km/h west ridgetop wind. Treeline temperature -5°C. Freezing levels valley bottom.

Thursday

A mix of sun and cloud. 10 to 30 km/h southwest ridgetop wind. Treeline temperatures near -1°C. Freezing level rising to 2000 m.

Friday

Sunny. Mostly light winds but in places gusty to 60 km/h from the northwest at ridgetop. Alpine temperatures high near +2°C. Freezing level rising to 3000 m.

Saturday

Sunny. 15 km/h northwest ridgetop wind. Alpine temperatures low of +2°C and a high of +6°C Freezing level rising 3200 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Avoid exposure to overhead avalanche terrain, avalanches may run surprisingly far.
  • Remote triggering is a concern, watch out for adjacent and overhead slopes.
  • If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
  • Brief periods of sun could quickly initiate natural avalanche activity.
  • Cornices become weak with daytime heating or solar exposure.

Problems

Persistent Slabs

An icon showing Persistent Slabs

A weak layer of facets rests above a hard-melt freeze crust that formed early February. Large natural avalanches have recently failed on this layer and it's primed for human triggering.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

2 - 3.5

Wind Slabs

An icon showing Wind Slabs

Southerly winds and new snow will add to the wind slab problem. These avalanches have the potential to step down to deeper weak layers.

Aspects: North, North East, East, West, North West.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Loose Wet

An icon showing Loose Wet

Even short periods of the strong March sun will weaken the snowpack. Especially on steep solar slopes.

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

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2

Valid until: Mar 14th, 2024 4:00PM