Avalanche Forecast

Issued: Feb 17th, 2014 8:05AM

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

ali haeri, Parks Canada

Glacier.

We have a big snow load overtop a very reactive weak layer down around 1m. Approach open slopes at all elevations with a great deal of caution.

Summary

Weather Forecast

Low off the coast of Alaska continues to bring inclement weather from the Pacific to the Interior. Light snow is expected today with westerly winds 20-30km/hr. More significant snowfall is forecast later tomorrow with associated strong west winds.

Snowpack Summary

20cm of new snow sits over 1m of settling recent storm snow from the past week. The Feb 10 facet/surface hoar layer and 2 late January surface hoar layers lie beneath this 1.2m slab. This interface has been the cause of numerous natural avalanches over the past week.

Avalanche Summary

6 natural size 3.0 slab avalanches yesterday as well as several size 2.0 to 2.5 slab avalanches within the highway corridor. Backcountry observations have been limited but riders can expect to see lots of evidence of recent natural activity.

Confidence

Intensity of incoming weather systems is uncertain

Problems

Storm Slabs

20cm of additional load overnight totalling 1.2m over a weak layer which has been very reactive this past week. Riders have reported cracking, whoomphing and avalanches on this layer. This is in addition to any shallower storm snow instabilities.

Whumpfing, shooting cracks and recent avalanches are all strong inicators of unstable snowpack.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 3

Wind Slabs

Winds from the current weather pattern have been steadily in the moderate to strong range. Expect to see more slabby conditions at higher elevations reactive to human triggering.

Avoid freshly wind loaded features.Be cautious as you transition into wind affected terrain.

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

2 - 3

Valid until: Feb 18th, 2014 8:00AM