Avalanche Forecast
Issued: Jan 21st, 2020 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs, Cornices and Deep Persistent Slabs.
mkoppang,
Avalanche Canada
Warm temps and strong winds have been a shock to the snowpack of late. Any change that happens quickly is rarely good. Lots of drummy windslabs out there at treeline and above. If they fail, good chance the basal layers will wake up.
Summary
Confidence
Weather Forecast
Light snow is forecast to begin overnight as temperatures begin to cool slightly. Winds are forecast to continue in the moderate range out of the SW. Freezing levels are forecast to be around 1200m with a mainly cloudy sky.
Avalanche Summary
No new avalanches were observed today.
Snowpack Summary
The snowpack is settling with the recent warm weather. Thin melt freeze crusts were observed on solar aspects this morning. Wind slabs are now widespread at all elevations and on all aspects except westerly. These slabs are of varying thickness and also have highly inconsistent results in snowpack stability tests. Forecasters continue to monitor the Dec 31 layer (surface hoar or facets) that is now buried 50cm on average. The layer has not been particularly active in avalanche activity, but it's a good thing to keep an eye on. The mid-pack is unusually strong and settled for this part of the mountain range. While, in many ways this is a good thing, it also serves to mask the significant basal weakness. There is still potential to trigger the basal layers, particularly in shallow snowpack areas, which could result in very large, destructive avalanches.
Terrain and Travel
- Avoid shallow, rocky areas where the snowpack transitions from thick to thin.
- Cornices become weak with daytime heating.
- Avoid thin areas like rock outcroppings where you're most likely to trigger avalanches failing on deep weak layers.
Problems
Wind Slabs
Windslabs are being observed in most open areas at treeline and above. Thick to thin spots are widespread throughout the region.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Cornices
Corncies have been observed to collapse lately in the heat.
Aspects: North, North East, East, South East.
Elevations: Alpine.
Likelihood
Expected Size
Deep Persistent Slabs
Deep basal avalanches are still possible in areas that have not yet released.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Jan 22nd, 2020 4:00PM
