Avalanche Forecast
Issued: Mar 18th, 2020 4:31PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Deep Persistent Slabs.
Lisa Paulson,
Parks Canada
Be mindful of prolonged solar input. It can suddenly increase the sensitivity of the problems described and/or cause cornices to fail, which may also trigger these problems.
Summary
Weather Forecast
The weather looks stable for the next few days. Thursdays temperatures ranging from -4 to -12 with cloudy skies and sunny periods, and light South winds. Even the 10 day forecast looks like very little new snow thankfully (given the current health situation...).
Snowpack Summary
Sun crust on steep solar aspects. Widespread wind effect in the alpine from recent multidirectional winds with 5 cm new snow on top. On sheltered Northerly aspects there is 15-20 cm over a firm mid-pack. In shallow snowpack areas the weak basal facets remain a concern.
Avalanche Summary
Several solar triggered small loose avalanches observed today. Otherwise, no new avalanches observed or reported on Wednesday. Our observations are very limited and we appreciate your reports to the MIN.
Confidence
Due to the number of field observations
Problems
Wind Slabs
Recent snow and variable wind directions (SW, N and E) have developed wind slabs in lee areas on a variety of aspects. These are beginning to bond but use caution if you encounter them in steep terrain, especially in thin snowpack areas.
- Variable winds may create pockets of wind slab in some unexpected locations.
- If triggered the wind slabs may step down to deeper layers resulting in large avalanches.
Aspects: All aspects.
Elevations: Alpine.
Likelihood
Expected Size
Deep Persistent Slabs
Use caution in thin snowpack areas averaging 150cm or less. In these areas the basal snowpack layer of depth hoar and facets remains weak, and the mid and upper snowpack is thin enough to allow for triggering of the deep persistent layer.
- Be aware of thin areas that may propogate to deeper instabilites.
- Pay attention to overhead hazards like cornices which could trigger the deep persistent slab.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Mar 19th, 2020 4:00PM
