Avalanche Forecast

Issued: Jan 22nd, 2018 4:00PM

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

deryl kelly, Parks Canada

Jasper.

Recent storm snow has made for good skiing at and above treeline in sheltered locations.

Summary

Weather Forecast

A strong SW flow with a series of low pressure storm cells tracking west from BC will give unsettled weather with light snow until later in the week. Tuesday: Cloudy with sunny periods/isolated flurries. Precip: 4cm. Alpine Low -13°C, High -8°C. Ridge wind moderate SW. Wednesday: Snow flurries, 9cm. Alpine temp: Low -8°C, High -4°C.

Snowpack Summary

Small amounts of new snow this week continue to add windslab above treeline. Early January surface hoar down 35cm, mid December facets down 50cm, and basal facets 20cm above ground are the main weak layers in the snowpack. Field teams had easy shear failures today on a SE open slope at treeline in the Icefields area down both 35cm and 50cm.

Avalanche Summary

Limited visibility with no new notable avalanche observations.

Confidence

Due to the number of field observations on Monday

Problems

Persistent Slabs

Well preserved surface hoar has been found in several treeline locations in the Icefields area. Shear tests were easy failures 35cm deep on this layer.

Be aware of the potential for avalanches due to buried surface hoar in isolated areas.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 2.5

Persistent Slabs

This layer is primarily weak facets and had easy failures at treeline in test profiles today down 40 to 50cm.

Watch for whumpfing, hollow sounds, and shooting cracks.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2.5

Wind Slabs

Small inputs of fresh storm snow with southwesterly winds continue to build small lenses of windslab in sheltered lee features.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Valid until: Jan 23rd, 2018 4:00PM