Avalanche Forecast
Regions:
Numerous very large deep persistent slab avalanches have been reported on a variety of aspects in the alpine.
Recent snow and southerly wind may have formed fresh wind slabs on lee features.
Confidence
Low
Avalanche Summary
No avalanches were reported on Sunday. However, observations in this region are currently very limited.
Numerous naturally triggered very large (up to size 3.5) deep persistent slab avalanches were reported on a variety of aspects in the alpine on Friday. They failed on either a crust/facet layer 100+cm deep or weak facets at the bottom of the snowpack. Follow the link on this MIN for the photos of these notable avalanches.
Observations are limited at this time of year, please consider sharing any information or photos you have on the Mountain Information Network to help guide our forecasts.
Snowpack Summary
Recent snow and southerly wind may have formed fresh wind slabs on lee features.
A weak layer of crust/facets down 100+ cm and/or weak facets at the bottom of the snowpack have recently become reactive.
Cornices are large and loom over slopes below like gargoyles.
Weather Summary
Monday Night
Mostly cloudy with flurries; 5-10 cm / 20 km/h south ridgetop wind / Temperature at treeline around -5 C / Freezing level valley bottom
Tuesday
Mix of sun and cloud / 30 km/h south ridgetop wind / Temperature at treeline around -3 C / Freezing level 700 m
Wednesday
Mix of sun and cloud with isolated flurries; 3-5 cm / 20 km/h southeast ridgetop wind / Temperature at treeline around -1 C / Freezing level 1000 m
Thursday
Cloudy with flurries; 5-10 cm / 50 km/h south ridgetop wind / Temperature at treeline around -1 C / Freezing level 1000 m
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- In areas where deep persistent slabs may exist, avoid shallow or variable depth snowpacks and unsupported terrain features.
- Watch for signs of instability like whumpfing, hollow sounds, shooting cracks or recent avalanches.
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
- Cornice failure may trigger large avalanches.
Avalanche Problems
Deep Persistent Slabs
A weak layer of crust/facets down 100+ cm and/or weak facets at the bottom of the snowpack have recently become reactive.
Snowpack and avalanche observation data are currently very limited in this region which makes this kind of avalanche problem very difficult to forecast.
Aspects: All aspects.
Elevations: Alpine.
Likelihood: Possible
Expected Size: 2 - 3.5
Wind Slabs
Recent snow and southerly wind may have formed fresh wind slabs on lee features.
Aspects: North, North East, East, West, North West.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 1 - 2
Cornices
Cornices are very large and loom over slopes below like gargoyles. Cornice falls may trigger large avalanches on the slopes below.
Aspects: North, North East, East, North West.
Elevations: Alpine.
Likelihood: Possible
Expected Size: 1.5 - 2.5