Avalanche Forecast

Issued: Jan 20th, 2017 4:03PM

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

mbender, Avalanche Canada

Purcells.

Continued unsettled weather for the region. However there is now significant snow forecast within the period.

Summary

Confidence

Moderate - Freezing levels are uncertain

Weather Forecast

SATURDAY: Cloudy with isolated flurries, wind light southeast, alpine temperature -8SUNDAY: Cloudy with isolated flurries, wind light south, alpine temperature -10MONDAY: Cloudy with isolated flurries, wind light west, alpine temperature -9More details can be found on the Mountain Weather Forecast.

Avalanche Summary

Recent reports indicate some explosives triggered avalanches to size 2 in the alpine on west and north aspects over the last few days.

Snowpack Summary

10-30 cm of recent new snow accumulation, wind and warming have built wind slabs on wind-loaded features. In sheltered areas, the new snow has possibly buried a layer of feathery surface hoar. The main concern deeper in the snowpack is a layer of sugary facets from mid-December that can be found between 50 and 100 cm deep. This layer was considered dormant during the the previous cold weather, but may still become reactive with the recent warm temperatures.

Problems

Wind Slabs

Recent new snow combined with southwest winds have created windslabs in the lee of terrain features

Be cautious as you transition into wind affected terrain.Use ridges or ribs to avoid pockets of wind loaded snow.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Persistent Slabs

Recent warming will have increased the likelihood of triggering persistent weak layers that have been lingering deeper in the snowpack

Be cautious in shallow snowpack areas where triggering is more likely.Carefully evaluate terrain features by digging and testing on adjacent, safe slopes.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Unlikely - Possible

Expected Size

2 - 3

Valid until: Jan 21st, 2017 2:00PM