Avalanche Forecast
Issued: Jan 20th, 2020 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Persistent Slabs.
kdevine,
Avalanche Canada
Pockets of wind slab may be encountered at upper elevations. Use caution around wind loaded features.
Summary
Confidence
Moderate - Uncertainty is due to the fact that persistent slabs are particularly difficult to forecast.
Weather Forecast
MONDAY NIGHT - Mainly cloudy with isolated flurries / south wind, 10-30 km/h / alpine low temperature near -3
TUESDAY - Flurries, 5-10 cm / south wind, 10-30 km/h / alpine high temperature near -2
WEDNESDAY - Cloudy with isolated flurries / southwest wind, 15-25 km/h / alpine high temperature near -4
THURSDAY - Flurries, 5-10 cm / southwest wind, 30-50 km/h / alpine high temperature near 0 / freezing level 1800 m
Avalanche Summary
Avalanche activity was pretty quiet on Sunday and Monday with one report of an explosives triggered size 2.5 loose snow avalanche.
On Thursday and Friday there were reports of numerous natural, human and explosives triggered size 1-2.5 storm and wind slab avalanches.
No new persistent slab avalanches were observed in the past few days, but this region has been highlighted for recent persistent slab avalanche activity. A number of natural and explosives triggered persistent slab avalanches up to size 3 were reported just over a week ago.
Snowpack Summary
Stormy weather over the past several days brought 35 to 65 cm of snow to the region with moderate to strong winds from a variety of directions. This, combined with recent warm temperatures, will have likely formed fresh storm slabs in many areas.
There are two weak layers of surface hoar found around 70 to 130 cm deep. These layers are especially concerning in steep, sheltered, large terrain features and shallow rocky areas.
The base of the snowpack is also weak in parts of the region where it consists of sugary faceted snow around a melt-freeze crust.
Terrain and Travel
- Be aware of the potential for large avalanches due to the presence of buried persistent weak layers.
- Avoid freshly wind loaded terrain features.
Problems
Wind Slabs
Previous new snow and wind has likely formed pockets of wind slab in lee terrain features.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
Several persistent weak layers are buried in the snowpack. It is possible for humans to trigger them, or for smaller avalanches to step down to them and form very large avalanches.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Jan 21st, 2020 5:00PM
