Avalanche Forecast

Issued: Jan 11th, 2014 4:49PM

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

a.l. horton, Parks Canada

Jasper.

The Icefields Parkway is closed due to high avalanche danger. It will not open until control work has been completed. The new storm snow is unstable and will need time to stabilize. Resist the urge and stick to safe lines on lower angle terrain!

Summary

Weather Forecast

The major storm has past however further amounts of up to 20-30 cm are possible by Monday night. Winds are expected to increase to strong from the W to NW. Temperatures will dip Sunday morning then rebound. Temperatures will increase to above freezing with the possibility of rain later in the week.

Snowpack Summary

>35cm of storm snow has fallen since Friday. Moderate SW winds have created deep soft slab conditions in the alpine and open TL slopes. In many locations, these new slabs are sitting on weak basal facets.

Avalanche Summary

Very poor visibility precluded avalanche observation however numerous large avalanches were heard through out the day from the Icefields to Sask Xing. Sluffing of storm snow on steep banks was observed as well as soft slab avalanches to sz 1.5 at treeline.

Confidence

Intensity of incoming weather systems is uncertain on Monday

Problems

Storm Slabs

>35 cm of storm snow has fallen in the past 24 hrs and has been redistributed by moderate SW winds. This new snow is overloading the weak snowpack below resulting in large deep avalanches.

Avoid avalanche terrain during periods of heavy loading from new snow and wind.The new snow will require several days to settle and stabilize.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Very Likely

Expected Size

1 - 4

Deep Persistent Slabs

In many areas, the basal facet weakness has been avalanched away, where this has not happened, there is a lot of snow sitting on top of this unstable weakness.

Be aware of thin areas that may propogate to deeper instabilites.Avoid steep, open slopes.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

2 - 4

Wind Slabs

These winds slabs have now been buried by the new snow so will be hard to locate.

Avoid ice climbs that are in terrain traps below large start zones.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Jan 12th, 2014 4:00PM