Avalanche Forecast
Issued: Dec 18th, 2019 3:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs and Persistent Slabs.
jfloyer,
Avalanche Canada
New snow and strong winds will result in CONSIDERABLE avalanche hazard, especially behind exposed ridges where wind slabs are likely to form. Increase the danger rating to HIGH for your area if 25 cm or more snow falls in a 24 hour period.
Summary
Confidence
Moderate - Forecast snowfall amounts are uncertain.
Weather Forecast
Wednesday night: 5-10 cm new snow. Moderate southwest winds. Treeline temperatures around -4C.
Thursday: approximately 5 cm new snow during the day, with additional snow in the evening. Moderate southwest winds. Freezing level rising briefly to 1000 m in the afternoon.
Friday: 10-20 cm new snow. Strong southwest winds. Treeline temperatures around -4C.
Saturday: Flurries. Moderate southwest winds. Treeline temperatures around -8C.
Avalanche Summary
We have not had any reports of avalanche activity at the time of writing (Wednesday afternoon). Natural avalanches are most likely to occur below steep ridgelines in higher snow parts of the region.
Snowpack Summary
20-40 cm of recent storm snow lies on the surface. You can expect to find three weak layers buried between 30 and 60 cm below the surface. These surface hoar and facet/crust layers have shown signs of being reactive in snowpack tests and could become unstable with the weight of additional snow.
The lower snowpack contains several crust layers. In higher snow areas, these are likely well bonded. However, in shallow areas along the eastern slopes, these could be of concern.
Total snowpack depths are approximately 240 cm in the south of the region, 170 cm around Pine Pass and more like 120 cm in areas to the east.
Problems
Storm Slabs
New snow and strong southwest winds will set up storm and wind slabs, particularly behind exposed ridges.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Persistent Slabs
Weak layers of surface hoar exist in the upper snowpack. These are most likely to be triggered on steep convex slopes at or below treeline that have not previously been well ridden.
Aspects: North, North East, North West.
Elevations: Treeline, Below Treeline.
Likelihood
Expected Size
Valid until: Dec 20th, 2019 5:00PM
