Avalanche Forecast

Issued: Dec 8th, 2014 8:28AM

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

jlammers, Avalanche Canada

South Rockies.

Observations have been extremely limited. If you have any snowpack or avalanche information you can upload it to our new Mountain Information Network. Check out the details at: http://www.avalanche.ca/blogs/VIYBuScAAJdbdqPz/m-i-n-intro

Summary

Confidence

Poor - Due to the number of field observations

Weather Forecast

Despite a strong southwest flow, only modest amounts of precipitation (about 5mm/day) are expected over the forecast period. Freezing levels are expected to peak at about 2300m on Tuesday and Wednesday, and then drop to about 1900m on Thursday. Strong southwest winds are forecast for the entire period.

Avalanche Summary

No avalanche activity reported. If you've witnessed any avalanches, please send a note to forecaster@avalanche.ca

Snowpack Summary

There is at least one, maybe more, problematic layers in the South Rockies snowpack. Last weekends 30 - 60cm of storm snow buried a weak layer of facets over a crust which formed during November's dry spell. That interface is probably around a meter down now. Not much is known about the reactivity of this layer, nor the slab above it. But, it doesn't take much of a leap of faith to understand that a meter deep slab sitting on a persistent weak layer is a potentially bad thing.

Problems

Wind Slabs

Strong winds have developed windslabs in the alpine and at treeline in areas with snow available for transport. Forecast new snow and wind may form new windslabs in exposed terrain.

Use ridges or ribs to avoid pockets of wind loaded snow.>Avoid freshly wind loaded features.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Persistent Slabs

A deeply buried crust with a weak layer of facets or surface hoar at the interface may exist in some parts of this region. Dig down and locate the crust, and then test how the upper snowpack is bonding to the crust.

Be aware of thin areas that may propogate to deeper instabilites.>Avoid convexities or areas with a thin or variable snowpack.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 5

Valid until: Dec 9th, 2014 2:00PM