Avalanche Forecast

Issued: Apr 5th, 2018 6:50PM

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

Alberta Parks mike.koppang, Alberta Parks

New snow is forecast to arrive over the weekend are temps are forecast to slowy rise.  Pay attention to localized winds as lots of snow is available for transport.

Summary

Confidence

High -

Weather Forecast

A mix of sun and cloud.Precipitation: Nil.Alpine temperature: High -6 °C.Ridge wind southwest: 15 km/h.Freezing level: 1700 metres.

Avalanche Summary

Forecaster were able to trigger a large cornice collapse while travelling along a ridge on Wednesday indicating that they are large and reactive to skiers.  Use caution around these beasts.  Otherwise, only loose dry avalanches up to sz 1 from steep unskiable terrain were observed.

Snowpack Summary

Surface facetting continues in the upper snowpack due to the cold temperatures.  This is certainly helping the ski quality!  Isolated windslabs are being encountered along ridgelines but do not extend far downslope.  Cornices are very large for this time of year.  Also the March 15th crust is down 40-60cm on solar aspects up to peaks and the bond with the overlying snow is variable.  Dig down and test this layer....A new thin melt freeze crust formed on solar aspects on Thursday that may make the skiing a little more...hooky and challenging.

Problems

Wind Slabs

An icon showing Wind Slabs
Wind slabs are being encountered along ridgelines in alpine terrain.  These slabs do not extend far downslope but are present in immediate lees. Use caution at the entrances to runs. 
Be careful with wind loaded pockets, especially near ridge crests and roll-overs.Evaluate unsupported slopes critically.

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

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 2.5

Persistent Slabs

An icon showing Persistent Slabs
The March 15th melt-freeze crust, buried 30-50cm on solar aspects, could be an issue on bigger slopes, particularly in the Alpine. Evaluate the snowpack for the presence/absence of this problem layer before committing to a terrain feature.
Avoid steep Southerly aspects.

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

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 2.5

Cornices

An icon showing Cornices
Cornices are large and looming over slopes at the moment. Keep an eye on these if the sun comes out. 
Give cornices a wide berth when travelling on or below ridges.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2.5

Valid until: Apr 6th, 2018 2:00PM