Avalanche Forecast

Issued: Feb 15th, 2022 4:00PM

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

Avalanche Canada TRettie, Avalanche Canada

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 The likelihood of triggering the late January layer is low but not impossible. Use extra caution on slopes where a thick supportive crust is absent. 

Summary

Confidence

Moderate -

Weather Forecast

Tuesday night: Light snow bringing up to 5cm with moderate northwest winds. Low of -6 at 1500m. 

Wednesday: A mix of sun and cloud with the possibility of some light flurries bringing trace amounts of snow. Light to moderate northwest winds and freezing levels rising to 1600m. 

Thursday: Cloudy with a chance of flurries bringing up to 5cm of new snow. Moderate northwest winds and freezing levels rising to 1400m.

Friday: cloudy with the possibility of light flurries. Light to moderate northwest winds and freezing levels rising to 1300m.

Avalanche Summary

On Monday a size two natural persistent slab avalanche was reported. This avalanche released in steep terrain on a northeast aspect at 1850m and ran on the late January layer. This avalanche likely occured on Sunday.

On Sunday, several natural cornices were observed in the north of the region, some of which triggered size 1-2 slabs on the slopes below. Around the Coquihalla, some glide slab avalanches were observed. Small loose wet avalanches were also observed from steep sun-exposed slopes throughout the region. 

Snowpack Summary

The new snow has buried a widespread surface crust and wind-affected surfaces in exposed high elevation terrain. The melt-freeze crust is reported to exist on all aspects and elevations except for some of the highest elevation polar aspects in the north of the region which may still hold dry snow. The crust was reported to be undergoing faceting in some areas prior to the snowfall. 

The late-January crust/facet/surface hoar interface is buried down 20-70 cm. This layer was most reactive between 1700 m and 2000 m in the north of the region. While this layer now appears to be dormant in many parts of the region, recent snowpack tests suggest it is still very reactive in a few places in the north of the region and would still be capable of producing large avalanches if triggered.

Terrain and Travel

  • Be aware of the potential for large avalanches due to the presence of buried persistent weak layers.
  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Wind slabs may be poorly bonded to the underlying crust.

Problems

Persistent Slabs

An icon showing Persistent Slabs

The late-January weak layer is down 20-70 cm and was most reactive between 1700 and 2000 m in the north of the region. It is now likely dormant in most areas, especially where there is a supportive surface crust. However, recent snowpack tests suggest it is still reactive and capable of producing large avalanches if triggered. We have now entered a low probability, high consequence scenario with this layer. 

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely

Expected Size

2 - 3

Wind Slabs

An icon showing Wind Slabs

Thin new wind slabs may have formed on Monday in the south of the region. These could be more reactive than normal given the hard crust they are sitting on. 

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 1.5

Valid until: Feb 16th, 2022 4:00PM