Avalanche Forecast

Issued: Mar 18th, 2014 3:00PM

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

Alberta Parks burke.duncan, Alberta Parks

Conditions remain ripe for human triggering of avalanches.  Watch for the effects of daytime heating along or above travel routes. A spike in Avalanche danger is possible by Thursday with incoming snowfall and winds.

Summary

Confidence

Fair - Intensity of incoming weather systems is uncertain on Thursday

Weather Forecast

Mainly clear skies tonight with Low -11 deg.  Winds west 35km/h.Wednesday - Trace of precip forecast with daytime high -5 deg.  Winds west 35 gusting to 60 km/h.  Looking forward to 15-20cm snow on Thursday.

Avalanche Summary

A few loose dry on N-NE aspects to Size 1 observed. Later in PM loose dry were becoming loose moist on steep rocky aspects triggering SSL to Size 1 on steeper planar slopes below.One Size 2.5 full depth slab release on steep NE aspect triggered by cornice failure. Failure plane was ground and ran full path to Smith-Dorrien creek bottom. Max depth in excess of 1 meter deep, up to 100m Wide and 300m in length. Daytime heating may be awakening the deep basal weakness.

Snowpack Summary

New suncrust beginning to form on steep solar exposed slopes. Storm snow is settling and bonding to previous surface but some concern related to windslab development still.

Problems

Persistent Slabs

An icon showing Persistent Slabs
This persistent weak layer is buried 70 to 100cm in Alpine and Treeline areas and is sensitive to human triggering. There is increasing potential for failure deeper in the snowpack as the weather warms!
Be aware of the potential for large, deep avalanches.>Avoid convexities or areas with a thin or variable snowpack.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

3 - 5

Wind Slabs

An icon showing Wind Slabs
Fresh wind slabs are found on lee and cross loaded features at treeline and above.  If these slabs are triggered an avalanche could step down to the Feb 10th layer or even deeper and produce a large avalanche. 
Avoid convexities or areas with a thin or variable snowpack.>Avoid cross loaded features.>Avoid freshly wind loaded features.>

Aspects: North, North East, East.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

2 - 4

Loose Dry

An icon showing Loose Dry
Becoming loose moist on steep solar aspects in PM.
Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 3

Valid until: Mar 19th, 2014 2:00PM