Avalanche Forecast
Issued: Dec 13th, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Persistent Slabs.
Kate Ryan,
Expect variable skiing in wind exposed terrain!
Soft turns can be found in sheltered areas below treeline.
Summary
Weather Forecast
After tonight's snow, unsettled weather remains bringing cloudy skies and scattered flurries.
Tonight: 4cm. Winds SE - 25-45km/h. Freezing level 600m
Tuesday: Trace of snow. Winds SE - 25-40km/h. Freezing level 1100m.
Wednesday: Trace of snow. Wind SW - 20-30km/h. Freezing level 600m.
Snowpack Summary
Rogers Pass received ~35cm of low density snow over the weekend. Extreme south winds created fresh slabs in exposed terrain features, further down into the path than you might expect. The Dec 1 crust is ~15cm thick at 1900m, buried by ~90cm and found up to 2300m. The mid and lower snowpack is generally well bonded and strong.
Avalanche Summary
No new avalanches were observed today in the highway corridor.
A natural avalanche cycle up to size 3 occurred Saturday with the new snow and strong winds. Cheops N1 ran size 2.0 and dusted the skin track in the Connaught Drainage.
There have been many reports of size 1-2 skier triggered slab avalanches in steep terrain and on convex rolls.
Confidence
Problems
Wind Slabs
35cm of new snow over the weekend was redistributed by extreme winds (up to 140km/h at Macondald West Shoulder weather station saturday!). These extreme wind events may create slabs where you wouldn't normally expect them.
- If triggered the wind slabs may step down to deeper layers resulting in large avalanches.
- Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
There is 50-90cm on the Dec 1st crust, which has been skier-triggered in thinner snowpack areas. It is mainly an issue at treeline, but also extends into the lower alpine region up to 2300m.
- Avoid steep convexities or areas with a thin or variable snowpack.
- Carefully evaluate terrain features by digging and testing on adjacent, safe slopes.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 14th, 2021 4:00PM
