Avalanche Forecast

Issued: Feb 28th, 2013 8:07AM

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

jon schleiss, Parks Canada

Glacier.

A strong Pacific storm is bringing warm temperatures, heavy precipitation and strong winds. Be aware of rapidly developing avalanche conditions when this storm arrives.

Summary

Weather Forecast

Light precipitation is forecast for today, and is going to be followed by a major storm this evening and for the next few days. This storm is being referred to as a "Pineapple Express" and is forecast to bring 20-25cm overnight, and another 20-30cm on Friday, with rising temperatures and freeze lines. Freezing levels are up to 1300m today.

Snowpack Summary

Top 40 cm settling storm snow with a soft breakable crust on top where it is exposed to the sun. Feb 12 surface hoar and crust layers down 50-60cm, fist to 1 finger snow over top. Mid pack is well settled.

Avalanche Summary

No new avalanches were observed in the park yesterday.

Confidence

Timing, track, or intensity of incoming weather system is uncertain

Problems

Persistent Slabs

Surface hoar layer buried 45-60cm. This layer is reactive to rider triggering and remote triggering and has been seen to be most reactive where the surface hoar is sitting on a sun crust or firm layer in the snowpack (bed-surface).

Avoid open slopes and convex rolls at and below treeline where buried surface hoar may be preserved.Be aware of the potential for large, deep avalanches due to the presence of buried surface hoar.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Storm Slabs

Instabilities in the upper 50cm from the recent storm snow can step down to the Feb 12 surface hoar layer.

Avoid all avalanche terrain during periods of heavy loading from new snow, wind, or rain.Dig down to find and test weak layers before committing to a line.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 3

Valid until: Mar 1st, 2013 8:00AM