Avalanche Forecast
Issued: Jan 3rd, 2020 5:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs and Persistent Slabs.
MBender,
Avalanche Canada
The snowpack will take time to adjust to the load from recent snowfalls. In the meantime continue to choose conservative terrain.
Summary
Confidence
Moderate - Forecast snowfall amounts are uncertain.
Weather Forecast
Friday Night: Flurries, accumulation 5-10 cm. Alpine temperature -4 C. Moderate to strong west wind. Freezing level 1200 m.
Saturday: Flurries, accumulation 5-10 cm. Alpine temperature -4 C. Moderate southwest wind. Freezing level 1400 m.
Sunday: Flurries. Alpine temperature -9 C. Moderate west wind.
Monday: Mainly cloudy with scattered flurries. Alpine temperature -6. Moderate southwest wind.
Avalanche Summary
There was a widespread natural and explosives triggered storm slab avalanche activity to size 2.5 and 3 on Wednesday and Thursday. Avalanches were 30-60 cm deep and were reported on all aspects and elevations. Additionally there were several human triggered avalanches reported up to size 2. Some of these were remotely triggered (from a distance). There was a skier remote triggered size 2.5 storm slab avalanche on Tursday in the very south of the region in at 2100 m on a north aspect. This is suspected to have run on surface hoar buried 45 cm deep.
Snowpack Summary
60-110 cm of new snow fell through the last week. All this recent snow has buried a layer of surface hoar found at all elevations. In some places the surface hoar may be combined with a crust on steep sun-exposed aspects.
Another weak layer that was buried around December 27 is a further 20-30 cm below and may present as surface hoar in sheltered areas, sun crust on steep solar aspects and/or a melt freeze crust below 1700 m.
An additional layer of surface hoar buried mid December is 130-200 cm deep. Avalanche activity on this layer has tapered off, but there is still concern for heavy loads to step down to this layer. A crust from late November is now over 200 cm deep. Concern for this layer is limited to rocky or variable snowpack depth areas in the alpine where it most likely exists as a combination of facets and crust.
Terrain and Travel
- Be alert to conditions that change with elevation and wind exposure.
- Avoid freshly wind loaded terrain features.
- Be aware of the potential for large avalanches due to the presence of buried persistent weak layers.
- Storm slabs in motion may step down to deeper layers resulting in large avalanches.
Problems
Storm Slabs
Snowfall continues to accumulate above a recently buried layer of weak surface hoar. Expect storm slabs to remain reactive as the load builds.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Persistent Slabs
There is still concern for heavy loads (storm slab avalanches running) to step down and trigger deeper weak layers buried in December.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Jan 4th, 2020 5:00PM
