Avalanche Forecast
Issued: Dec 27th, 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.
ahanna,
Avalanche Canada
Keep an eye on steep south facing slopes for solar triggered point releases in recent snow Monday afternoon.
We know you're out there! Please share your observations with us on the Mountain Information Network (MIN) ��
Summary
Confidence
Low - Uncertainty is due to the limited number of field observations.
Weather Forecast
Sunday night: Partly cloudy, light southwest wind, alpine temperature -7 C, freezing level valley bottom.
Monday: Sun and cloud, light northwest wind, alpine temperature -4 C, freezing level 500 m.
Tuesday: Increasing cloud, moderate southwest wind, alpine temperature -5 C, freezing level 500 m.
Wednesday: Flurries, moderate southwest wind, alpine temperature -6 C, freezing level 500 m.
Avalanche Summary
No recent reports of avalanche activity.
A few persistent slab avalanches were reported last week, mostly in the north of the region near the Hurley, but also near Allison Pass. They were triggered by riders, heavy machinery, and naturally. The slabs were generally 60 to 90 cm deep, around 2000 m, and released on the weak layers described in the snowpack summary.
We know you're out there! Please share your observations with us on the Mountain Information Network (MIN)! Photos are especially helpful. Thanks for all the great MINs submitted so far.
Snowpack Summary
5-15 cm of recent snow has seen some redistribution by wind, resulting in good riding quality on lee aspects in the Coquihalla area, according to the great MIN reports we've received. (If you're going out in the Duffey, please share your observations on the MIN!) Below treeline, recent snow may be sitting over surface hoar.
A hard melt-freeze crust from early December is found around 40 to 120 cm deep in the snowpack. This crust may have weak layers above it, consisting of feathery surface hoar or sugary faceted grains. These weak layers are most prevalent in the north (e.g., Duffey Lake, Hurley) and found to a lesser extent in the south of the region. The snowpack should be treated as suspect anywhere you find either surface hoar or faceted grains above the crust.
The remainder of the snowpack is well-settled in the south of the region. In the north, another melt-freeze crust with associated faceted grains around it may be found near the ground. Without evidence of recent avalanche activity, the layer appears to be dormant at this time.
Terrain and Travel
- Minimize exposure to steep, sun exposed slopes, especially when the solar radiation is strong.
- Be careful with wind slabs, especially in steep, unsupported and/or convex terrain features.
- Be aware of the potential for large avalanches due to the presence of a persistent slab.
Problems
Wind Slabs
WInd loaded pockets below ridge crests and rollovers may be reactive to human triggers.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
Weak layers of surface hoar and/or faceted grains may be found above a hard melt-freeze crust. Recent reports suggest the weak layers may be less prevalent in the south of the region, but still exist in localized pockets.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Dec 28th, 2020 4:00PM
