Avalanche Forecast
Issued: Jan 25th, 2022 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Persistent Slabs.
Chris Gooliaff,
Natural avalanche activity has tapered off, but the deep instabilities within the snowpack are still present.
Shallow snowpack areas and unsupported slopes are trigger points to be avoided.
Summary
Weather Forecast
The forecast shows a quiet weather week, with calm in this stormy part of the world.
Tonight: cloudy, Alp low -10*C, mod SW winds
Wed: sun and cloud, Alp high -7*C, light NW ridgetop winds
Thurs: sun and cloud, Alp high -3*C, light SW winds
Fri: cloud, Alp high -4*C, mod SW winds
Snowpack Summary
Wind-affect can be found at treeline and above, varying from soft to hard slab, and recognized by a striated/rippled surface. The Jan 20th (2-4mm) surface hoar sits 30-35cm down, while the Jan 11 (2-5mm) surface hoar is down ~70-90cm. The Dec 1 crust/facet combo is down ~1.5 - 2.5m and will require a large trigger to come alive.
Avalanche Summary
No new avalanches observed in the highway corridor nor in the Sir Donald/Avalanche Crest area on Tuesday, Jan 25. A field team in the Sir D/Avalanche Crest zone ski-cut small features to 40* with no results.
Control work on Sunday produced results up to sz 3, one of which stepped down to the Dec 1st layer.
Confidence
Problems
Wind Slabs
Previous moderate winds formed slabs in the Alpine and down into Treeline. These slabs sit on the Jan 20th surface hoar and could be sensitive to human triggering. Lee features up high along ridges and steep, unsupported slopes require respect.
- If triggered the wind slabs may step down to deeper layers resulting in large avalanches.
- Convex features and steep unsupported slopes will be most prone to triggering.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
Several persistent weak layers (see snowpack summary) in the upper 1m have recently been active and, in some instances, stepped down to the deeper Dec 1 crust/facet layer. Investigate the snowpack before committing to your line.
- If triggered the persistent slabs may step down to deeper layers resulting in very large avalanches.
- Be wary of slopes that did not previously avalanche
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Jan 26th, 2022 4:00PM
