Avalanche Forecast

Issued: Dec 20th, 2019 4:00PM

The alpine rating is high, the treeline rating is high, and the below treeline rating is considerable.

mmueller, Avalanche Canada

We are in the middle of the first real storm of the year. This will stress the snowpack and likely cause a widespread avalanche cycle by Friday night. Avoid avalanche terrain tomorrow.

Summary

Confidence

No Rating -

Weather Forecast

For tonight and tomorrow, temperatures will be around -5. High alpine winds will be 60-100km/hr tonight and tomorrow. Gusts are expected up to 120km/hr. Ridgetop winds will less, but still plenty strong to transport snow. The snow is expected to keep going tonight and tomorrow. Forecasts vary, but 40cm seems to be the average.

Avalanche Summary

Numerous ski cuts easily produced avalanches. The biggest was a sz2. This was the maximum size the slope would allow. In more than one instance, the cracks traveled for 80m. These mostly involved the new storm snow, but in one case, there was a failure mid pack on an old windslab interface.Â

There was almost certainly natural activity, but the visibility kept us from seeing it.

Snowpack Summary

Up to 25cm as of 2pm today on the Spray Road. This new snow is relatively warm and is building storm slabs at all elevations. These were touchy today with reactive ski cuts on steep rolls. Lots of cracking in all areas and elevations. Some were shooting 30-40 feet. Treeline and alpine also has a widespread windslab that is equally reactive. The mid pack and bottom layers are basically weak facets that aren't bonding quickly to the new snow. The overall snowdepth varies between 80-130 at treeline.

Terrain and Travel

In areas where deep persistent slabs may exist, avoid shallow or variable depth snowpacks and unsupported terrain features.

Valid until: Dec 21st, 2019 4:00PM