Avalanche Forecast

Issued: Feb 17th, 2013 4:00PM

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

Parks Canada a.l. horton, Parks Canada

Solar triggering of the storm snow is possible with prolonged periods of sun.

Summary

Weather Forecast

Monday will be mainly dry, variable clouds and light North winds with cold air.  Tuesday, a weak pulse of 2-4 of new snow, the freezing level will rise to 1100 m and winds will remain light from the North.

Snowpack Summary

20 cm of storm snow are developing soft windslab on SE alpine and treeline slopes from moderate NW winds.  These new slabs are sitting on previous hard slab and sastrugi.  They appear to be bonding well.  The now buried hard slab is bridging weak basal facets.  15 cm of storm snow is sitting on sun crusts and facets below treeline.

Avalanche Summary

A couple of small slab avalanches (size 1.5) involving the new storm snow were observe Sunday morning on steep NE facing treeline slopes in the Parkers Ridge area.  No other avalanches were observed along the Icefields Parkway.  Visibility was excellent.

Confidence

The weather pattern is stable on Monday

Problems

Storm Slabs

An icon showing Storm Slabs
Up to 20 cm of new snow fell in the last storm. Moderate NW winds are pressing the new snow into soft slabs and building thin soft windslab on immediate lee features. These new storm slabs are sitting on smooth hard slab and sastrugi. 
Use caution in lee areas in the alpine. Recent wind loading have created wind slabs.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Valid until: Feb 18th, 2013 4:00PM