Avalanche Forecast

Issued: Feb 27th, 2015 7:55AM

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

rbuhler, Avalanche Canada

Northwest Inland.

Use increased caution on sun exposed slopes during the afternoon warming.Are you a member of Avalanche Canada? Join today at avalanche.ca/membership

Summary

Confidence

Fair - Timing or intensity of solar radiation is uncertain

Weather Forecast

A ridge of high pressure is the dominate feature for the next three days resulting in dry and sunny conditions. On Saturday, freezing levels are expected to be 600-1000m.Â Alpine winds are forecast to be moderate-to-strong from the N-NW. On Sunday, freezing levels should be around 600m. Alpine winds are forecast to remain moderate-to-strong from the N-NW. On Monday, strong-to-extreme outflow winds are forecast with the advancing of an arctic front.

Avalanche Summary

Some loose sluffing has been reported but no new avalanches. Avalanches are generally not expected on Saturday but small loose sluffing from steep sun exposed slopes is possible during the afternoon.Â Last week several full-depth avalanches up to Size 3 were observed on all but North aspects. As we get increased sun and warming heading into the weekend, these types of large isolated avalanches could once again become a problem.

Snowpack Summary

A dusting of new snow has buried the previously variable snow surface which may have included wind-pressed surfaces or old wind slabs, a sun crust or old rain crust, surface hoar, and/or surface facets. A layer of surface hoar buried in the upper snowpack has been reported in some areas and is worth investigating before committing to any big alpine terrain. At the base of the snowpack, weak facets may be persisting.

Problems

Wind Slabs

Strong outflow winds have caused reverse loading and thin wind slab formation. Use extra caution as you transition into wind affected terrain.

Be cautious as you transition into wind affected terrain.>

Aspects: North, North East, East, South East.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2

Deep Persistent Slabs

This is a low probability problem with large consequences. A weak basal layer resulted in several full depth avalanches during the last sunny period which could be repeated this weekend. Avoid steep, sun exposed slopes during the afternoon.

Avoid steep unsupported planar slopes when the solar radiation is strong.>Be aware of the potential for full depth avalanches due to deeply buried weak layers.>

Aspects: North, North East, East, South East, South.

Elevations: Alpine, Treeline.

Likelihood

Unlikely

Expected Size

3 - 5

Valid until: Feb 28th, 2015 2:00PM