Avalog Join
Archived

Avalanche Forecast

Nov 29th, 2017–Nov 30th, 2017
Alpine
3: Considerable
The avalanche danger rating in the alpine will be considerable
Treeline
2: Moderate
The avalanche danger rating at treeline will be moderate
Below Treeline
1: Low
The avalanche danger rating below treeline will be low
Alpine
3: Considerable
The avalanche danger rating in the alpine will be considerable
Treeline
2: Moderate
The avalanche danger rating at treeline will be moderate
Below Treeline
1: Low
The avalanche danger rating below treeline will be low
Alpine
3: Considerable
The avalanche danger rating in the alpine will be considerable
Treeline
2: Moderate
The avalanche danger rating at treeline will be moderate
Below Treeline
1: Low
The avalanche danger rating below treeline will be low

Regions: South Rockies.

There are few reports from the region at this time but we suspect there are windslabs at treeline and above, as well as one or more deeper weak layers buried in the snowpack. Use a conservative approach, and please post your observations to the MIN.

Confidence

Low - Due to the number and quality of field observations

Weather Forecast

THURSDAY: Mainly cloudy. Light to moderate west wind. Alpine temperature -7. Freezing level 1000 m.FRIDAY: Mainly cloudy. Light to moderate west wind. Alpine temperature -8. Freezing level 1000 m.SATURDAY: Mix of sun and cloud. Light to moderate west wind. Alpine temperature -6 Freezing level 1200 m.

Avalanche Summary

There have been no recent reports of avalanche activity in the region. However observers in Kananaskis Country report reactive, wind slabs on easterly aspects in the alpine producing small avalanches as well as persistent slab activity to Size 2.5 initiating on weak layers at or near the base of the snowpack in the alpine and running to treeline. To the south the deep October layers may be less of concern thanks to the rains from last week however wind slabs at upper elevations are likely to be easily triggered on lee and cross loaded slopes.

Snowpack Summary

There is little to no information regarding snowpack structure within the region. It is suspected however, that the upper snowpack consists of 10-50 cm of recent storm snow above a series of crusts, the most recent being the November 26 crust which is likely to be found up to 2550m elevation. Below this is a thin layer of low density snow then the November 23 crust which also suspected to exists to about 2450 m elevation. A third crust from late October (October 31) can likely be found around mid-pack depths and is believed to be approximately 5-10 cm thick with a layer of weak, sugary snow crystals above and below. This October 31 "crust/facet combo" has been identified as a failure layer in recent avalanche reports from the Kananaskis area to the north will likely remain a concern for northern regions of the South Rockies as well. Finally the early season early October rain crust lies near the base of the snowpack with 10-20 cm of facets below.

Avalanche Problems

Wind Slabs

Windslabs up to 30 or 40 cm thick can liklely be found at treeline and above on lee and cross-loaded slopes.
If triggered the wind slabs may step down to deeper layers resulting in large avalanches.Use caution in lee areas. New snow and wind loading have created wind slabs.

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

Elevations: Alpine, Treeline.

Likelihood: Likely

Expected Size: 1 - 2

Persistent Slabs

There are several crusts now buried within the snowpack. Be extra caution in thin snowpack areas where it may be possible to trigger a deeper layer and assume that a release near the surface may also have the potential to step-down to a deeper layer.
Be aware of thin areas that may propogate to deeper instabilites.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 3