Avalanche Forecast

Issued: Mar 7th, 2024 4:00PM

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

Avalanche Canada jpercival, Avalanche Canada

Email

Dangerous conditions persist. Manage the uncertainty around buried weak layers by sticking to low-angle terrain, avoiding overhead hazard, and communicating with groups around you.

Summary

Confidence

Moderate

Avalanche Summary

On Wednesday a naturally triggered size 1.5 persistent slab avalanche was observed in the alpine on a west aspect. Another persistent slab, size 1.5, was skier-triggered in the Hurley area on Tuesday. It was 80 cm deep and occurred on a northeast-facing roll at treeline.

Recent natural activity has been reported on north and west facing slopes at treeline and above to size 2.5 (large). This MIN gives a snapshot in the Wendy Thompson area.

Snowpack Summary

Light new snow amounts, thin surface crusts (on solar aspects) and new surface hoar growth have begun to change the snow surface. Otherwise, 50 - 90 cm of recent storm snow is continuing to settle over a facet/surface hoar/crust layer directly beneath it.

Just below, an older, more problematic combination layer of faceted snow over a thick crust is now 80-140 cm deep. This layer is the primary avalanche concern in the region, continuing to show sensitivity to human triggers and produce concerning snowpack test results. The snowpack below this layer is well settled and strong.

Weather Summary

Thursday night

Mainly cloudy. 5-10 km/h southwest or west alpine winds. Freezing level to valley bottom.

Friday

Cloudy with isolated flurries, 1-5 cm. 60-90 km/h southwest alpine winds. Treeline temperature -1 °C with freezing level to 1500 m.

Saturday

Cloudy with snowfall 5-15 cm. 40-50 km/h southwest alpine winds. Treeline temperature -1 °C with freezing levels rising to 1600 m.

Sunday

Cloudy with continuing flurries bringing 1-5 cm of new snow,. 30-50 km/h south alpine winds, easing. Treeline temperature -3 with freezing level falling from 1600 to 1400 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Fresh snow rests on a problematic persistent slab, don't let good riding lure you into complacency.
  • Remote triggering is a concern, watch out for adjacent and overhead slopes.
  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.

Problems

Persistent Slabs

An icon showing Persistent Slabs

Buried weak layers are most concerning at treeline elevations. Small avalanches may step down to this layer resulting in very large, destructive avalanches.

Use low-angle, simple terrain to help manage this problem.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1.5 - 3

Wind Slabs

An icon showing Wind Slabs

Recent storm snow may still react as a slab in wind affected features at higher elevations. Watch for deeper and more reactive slabs near ridgelines.

Recent north winds mean new slabs may be found on a range of aspects.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Mar 8th, 2024 4:00PM