Avalanche Forecast

Issued: Jan 4th, 2019 3:27PM

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

Alberta Parks matt.mueller, Alberta Parks

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Lots of new snow and wind have upped the hazard significantly. Giving the snow atleast a day or two to settle would be wise if heading into steep treeline or alpine features. Avoid any exposure to overhead slopes, avalanches may reach valley bottom.

Summary

Confidence

High -

Weather Forecast

The storm is expected to taper tonight. By tomorrow there will be mostly cloudy skies with a few early morning flurries. Alpine winds will continue to be in the moderate to high range. Temperatures will be slightly cooler tomorrow with a daytime high of -8 to -10.

Avalanche Summary

Only 1 sz2 slab was noted today on a north facing alpine area. Poor visibility prevented a good look around. It is safe to say that there is a widespread cycle ongoing in the alpine, with a specific cycle at treeline. Wind prone areas at treeline are suspect.

Snowpack Summary

As of this afternoon, the storm has left 25cm of settled snow at 2250m. This puts the total treeline snow depth to 120cm.  So far the winds haven't touched the lower treeline area, but the upper treeline and alpine areas have seen a fair bit of wind and widespread slabs. The deeper instabilities (Dec 10 and Oct 26) are very pronounced and basically make up the entire bottom third. The exact burial depth of this interface will vary depending on aspect (wind loading) and elevation. The trick with this snowpack will be identifying where there is a wind slab or not. Once the storm snow has "slabbed" up expect things to become very touchy. Avalanches stepping down and/or entraining loose snow are probable.

Problems

Wind Slabs

An icon showing Wind Slabs
Cracking and whumpfing tell us these slabs are reactive to skiers. Use small terrain features to constantly evaluate the snowpack as you travel higher. Thin, transitional areas should be treated with caution.
If triggered the storm/wind slabs may step down to deeper layers resulting in large avalanches.Avoid freshly wind loaded features.Avoid convexities or areas with a thin or variable snowpack.

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

Elevations: Alpine, Treeline.

Likelihood

Very Likely

Expected Size

1.5 - 2.5

Deep Persistent Slabs

An icon showing Deep Persistent Slabs
The new snow load had not improved this layer. It is as delicate as ever. Do not underestimate its avalanche potential!
Be aware of the potential for full depth avalanches due to weak layers at the base of the snowpack.Remote triggering is a concern, watch out for adjacent slopes.

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

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

2 - 3

Valid until: Jan 5th, 2019 2:00PM