Avalanche Forecast

Issued: Dec 6th, 2018 4:27PM

The alpine rating is low, the treeline rating is low, and the below treeline rating is low. Known problems include Wind Slabs.

shorton, Avalanche Canada

South Rockies.

While unlikely, it may be possible to trigger large avalanches in steep, smooth, alpine bowls where a dense slab rests on a weak base. Watch for isolated wind slabs near ridgecrest in the alpine too.

Summary

Confidence

Moderate - Due to the quality of field observations

Weather Forecast

This benign blocking pattern will be with us for the foreseeable future. Things begin to change on the Coast this weekend, but no precipitation is expected to make it to the South Rockies.THURSDAY NIGHT: Freezing level at valley bottom, light northwest wind, no significant precipitation.FRIDAY: Local valley cloud, alpine high temperatures around -10 C, light to moderate wind out of the west, no significant precipitation.SATURDAY: Scattered cloud cover, alpine high temperatures around -10 C, light wind out of the west, no significant precipitation.SUNDAY: Scattered cloud cover, alpine high temperatures around -8 C, moderate to strong wind out of the southwest, no significant precipitation.

Avalanche Summary

No new avalanches have been reported in the region. Small wind slabs have been reported in neighboring regions. If you have been out, please submit any observations to the Mountain Information Network MIN.

Snowpack Summary

The region received up to 20 cm of snow over the past seven days. Isolated pockets of stiff wind slab may exist on leeward slopes. On sheltered slopes in the alpine and at treeline, recent snow may be sitting above a weak surface hoar layer.A mixed layer of crusts and sugary facets buried in late October can be found at the base of the snowpack. This layer has not been active, but terrain features like smooth alpine bowls with variable snowpack depths are still suspect.Average snowpack depths at treeline are near 50 cm and taper quickly as elevation decreases.

Problems

Wind Slabs

Wind slabs are likely growing old and tired, but this a classic Rockies scenario where wind loaded features are some of the only rideable pieces of terrain. Human triggering would be most likely immediately lee of ridgecrest and in extreme terrain.

Be careful with wind loaded pockets, especially near ridge crests and roll-overs.Increase your caution as you transition into wind affected terrain.If triggered the wind slabs may step down to deeper layers resulting in large avalanches.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 1.5

Valid until: Dec 7th, 2018 2:00PM