Avalanche Forecast
Issued: Mar 3rd, 2020 4:00PM
The alpine rating is Wind Slabs, Cornices and Deep Persistent Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeMore snow and wind are on the way. Avalanche hazard is trending up.
Summary
Confidence
Moderate -
Weather Forecast
10 to 15cm of new snow is expected by Wednesday morning along with strong to extreme SW winds. Temperatures will range from -5 to -10 in the Alpine. Thursday looks like a mostly sunny day before another snow storm arrives Friday.
Avalanche Summary
Very limited observations today, but one large avalanche was noted off an eastern aspect of Grotto Mountain today around 2pm. The slide was difficult to see, but the powder cloud extended from ridgetop to valley bottom, so it is estimated that this was a size 2 to 2.5 wind slab avalanche initiated by wind loading.
Snowpack Summary
Up to 5cm in the past 24 hours adds to the recent storm snow totals of nearly 30cm. This recent snow has been redistributed by persistent strong to extreme SW winds. Expect wind slabs in virtually all terrain features except the most sheltered of areas. These wind slabs are reactive to skier triggering in steeper terrain. Cornices are also quite large, and more failures have occurred in recent days. Otherwise the mid pack remains dense and strong in traditionally thicker snowpack areas (generally further west closer to the divide). The basal facets remain a concern in the back of our mind as they appear to be with us for the entire season.
Terrain and Travel
- Avoid freshly wind loaded terrain features.
- Avoid lee and cross-loaded terrain.
- Avoid exposure to slopes that have cornices overhead.
- Be aware of the potential for large avalanches due to the presence of buried persistent weak layers.
Problems
Wind Slabs
Up to 30cm of recent snow coupled with persistent strong to extreme SW winds have created extensive wind slabs. These are sensitive to human triggering and some natural avalanche activity has been observed.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Cornices
Avalanches are large and looming. A large cornice failure could awaken the deeply buried basal facet layer resulting in very large avalanches.
Aspects: North, North East, East, South East, South.
Elevations: Alpine.
Likelihood
Expected Size
Deep Persistent Slabs
This problem could be awakened by a large trigger such as a cornice failure or a wind slab. Be especially cautious in shallow snowpack areas where triggering will be more sensitive.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Mar 4th, 2020 4:00PM