Avalanche Forecast

Issued: Feb 20th, 2020 4:00PM

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

Avalanche Canada mconlan, Avalanche Canada

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One more quiet weather day before stormy weather reaches the region over the weekend. Remember that low hazard does not mean no hazard; pockets of wind slabs may still be found in the region. In the north, shallow slabs could act as a trigger for buried weak layers.

Summary

Confidence

High - Confidence is due to a stable weather pattern with little change expected.

Weather Forecast

THURSDAY NIGHT: Clear skies, light to moderate southwest wind, alpine temperature -5 C, freezing level 800 m.

FRIDAY: Mix of sun and cloud, moderate southwest wind, alpine temperature -5 C, freezing level 1300 m.

SATURDAY: Cloudy with light snowfall, accumulation 2 to 5 cm, light to moderate southwest wind, alpine temperature -6 C, freezing level 1000 m.

SUNDAY: Cloudy with snowfall, accumulation 5 cm, moderate southwest wind, alpine temperature -8 C, freezing level 800 m.

Avalanche Summary

A few small, loose avalanches were triggered out of steep rocky terrain from solar warming on Wednesday. Otherwise, no new avalanches were observed.

Snowpack Summary

Clear skies have formed a melt-freeze crust on sun-exposed aspects and allowed for widespread surface hoar growth. Soft, faceted snow is found on shaded and sheltered aspects, which overlies hard surfaces and potentially buried surface hoar in sheltered terrain around treeline. Isolated wind slabs may still linger in steep, lee terrain features in the alpine.

The midpack is well-settled.

In the north part of the region (e.g. Duffey/Hurley/Goldbridge), a deep instability exist in the snowpack, consisting of a weak basal facet-crust complex. Sporadic avalanche activity on this layer is keeping it on our radar. In the south of the region, including the Coquihalla and Manning areas, there are no concerns about deeply buried weak layers.

Terrain and Travel

  • Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet
  • Pay attention to cornices and give them a wide berth when traveling on or below ridges.
  • If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.

Problems

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

In the north of the region (e.g. Duffey, Hurley, Goldbridge), a buried weak layer lingers in the snowpack. The likelihood of triggering the layer is low right now with relatively benign weather, but if you were to do so it would likely be in a shallow and rocky start zone. The likelihood will increase with a changing weather pattern this weekend.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely

Expected Size

2.5 - 3.5

Valid until: Feb 21st, 2020 5:00PM