Avalanche Forecast

Issued: Mar 25th, 2014 3:00PM

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

Alberta Parks burke.duncan, Alberta Parks

Another system bringing snow beginning Tuesday night.  Totals amounts of 30-40cm by Thursday  with moderate westerly winds will  result in additional load on the Feb 10 layer and will be capable of producing some larger avalanches. 

Summary

Confidence

Fair - Timing, track, or intensity of incoming weather system is uncertain on Wednesday

Weather Forecast

Current forecasts are showing snow beginning tonight with 30-40cm possible by late on Thursday.  Winds will increase to moderate out of the west.  Freezing levels will drop to approx 1500 meters.

Avalanche Summary

Isolated sluffing from steep alpine terrain.  Two Size 2.5 and one Size 3 natural have occurred in the past 24 hours  One of the Size 2.5 on Mt Murray was triggered by a cornice failure and caused a sympathetic release on an adjacent slope which ran full path to near the bottom of the runout.  The failure plane was the Feb 10 interface.  The second Size 2.5  initiated in a steep shallow rocky area and ran on ground.

Snowpack Summary

Surface hoar growth noted in sheltered areas below treeline with some surface facetting also observed.  Solar aspects have a thin crust from Monday that is becoming moist by midday.  The previous storm snow has settled into a soft slab 20-40cm thick in the alpine and open areas at treeline in immediate lee features - so far they appear to be well bonded to previous surfaces.  The Feb 10 layer is down anywhere from 80-120cm and is still producing sporadic natural and human triggered avalanche activity.

Problems

Persistent Slabs

An icon showing Persistent Slabs
The feb 10 layer is down 80-120cm and remains a concern.  Sporadic  avalanche activity still occurring on this layer with potential for large avalanches to occur.
Be aware of the potential for large, deep avalanches.>Avoid convexities or areas with a thin or variable snowpack.>Avoid shallow snowpack areas where triggering is more likely.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 5

Wind Slabs

An icon showing Wind Slabs
Windslabs are present in the immediate lees along ridgetops and in crosssloaded features in the alpine and open areas at treeline.
Caution in lee and cross-loaded terrain near ridge crests.>Avoid convexities or areas with a thin or variable snowpack.>Avoid freshly wind loaded features.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Valid until: Mar 26th, 2014 2:00PM