Avalanche Forecast
Issued: Jan 29th, 2023 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs, Persistent Slabs and Deep Persistent Slabs.
MH,
Avalanche Canada
Wind slabs can be found in the alpine and at tree line. If triggered, they could step down to deeper layers.
Cold temperatures are adding to the risks of backcountry travel, bring warm layers and leave yourself extra time to get out safely at the end of the day.
Summary
Confidence
Moderate
Avalanche Summary
Several skier-triggered sz 1-1.5 avalanches were reported over the last few days on Avalanche Crest, Hermit Slide path, and Swiss Couloir.
A natural cornice failure triggered a size 3 deep persistent slab on the SE slope of Grizzly Peak on Saturday.
Artillery control on Friday produced numerous size 2-2.5 and a few size 3 slab avalanches throughout the Park.
Snowpack Summary
Recent variable winds have created new wind slabs in the alpine and down into tree line.
The early Jan surface hoar is buried 40-70cm and is most prevalent at tree line. The November 17th facet weakness can still be found near the base of the snowpack in many areas.
Weather Summary
The ridge of high pressure will start to break down as a weak low pushes into the area. Expect a mix of sun and cloud on Monday, with 15-35km/hr Westerly winds and an alpine high of -15.
5cm of snow on Tuesday with gradually warming temperatures.
Terrain and Travel Advice
- Be careful with wind slabs, especially in steep, unsupported and/or convex terrain features.
- Carefully assess open slopes and convex rolls where buried surface hoar may be preserved.
Problems
Wind Slabs
Wind slabs have been encountered along ridgelines and on slopes immediately below from moderate winds from various directions over the last few days. If triggered, wind slabs may step down to the persistent surface hoar layers.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
This layer has been most reactive around treeline, in areas that have not seen significant skier traffic since early January.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Deep Persistent Slabs
After a long period of dormancy in the park, there was a large cornice triggered natural avalanche on Saturday on this low probability/high consequence layer. Watch for steep, thin, rocky areas where this layer could be triggered from.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Jan 30th, 2023 4:00PM
