Avalanche Forecast

Issued: Mar 20th, 2016 4:00PM

The alpine rating is moderate, the treeline rating is moderate, and the below treeline rating is moderate. Known problems include Persistent Slabs, Loose Wet and Cornices.

max darrah, Parks Canada

Jasper.

Solar influence, overhead cornice failure or isolated loading or cross-loading will affect the localized hazard as we approach spring like conditions.

Summary

Weather Forecast

Mild temperatures with freezing levels remaining at treeline with poor overnight recovery (re-freezing). Light Southwest winds with light scattered flurries amounting to up to 10cm by Monday evening then tapering off. Temperatures expected to drop by Tuesday evening.

Snowpack Summary

The snowpack is generally shallow and poorly consolidated, significant variation exists within the forecasting area. The persistent slab may still be active in the Portal Creek area. This layer could be triggered from thin spots on the slope (trees, rocks, etc). Alpine wind slab is present on lee slopes. Springlike conditions below tree-line.

Avalanche Summary

Significant large avalanches reported for field teams in the Icefields area. Appear that the most significant of which have been triggered by cornice failure up to sz 3.5 in the Alpine in the past 72 hours.

Confidence

Problems

Persistent Slabs

This problem may still be a concern in the Whistler/Portal Creek area. It appears to be inactive in the Maligne and Icefields areas.

Avoid slopes when the solar radiation is strong, especially if they have large cornices overhead.Be aware of thin areas that may propogate to deeper instabilites.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

2 - 3

Loose Wet

Freezing level expected to remain at treeline throughout the next 48 hours, even overnight. Expect sluffing and loose wet activity during the heat of the day, particularly on solar aspects.

Minimize exposure to steep, sun exposed slopes when the solar radiation is strong.Avoid ice climbs that are in terrain traps below large start zones.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Cornices

First indicators of this problem showing up. Easy enough to avoid but, larger slides, triggered in the deep weaknesses can easily become a significant issue for groups traveling in the valley bottoms or run outs.

Avoid slopes when the solar radiation is strong, especially if they have large cornices overhead.Minimize exposure to overhead avalanche terrain, large avalanches may reach run out zones.

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

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 4

Valid until: Mar 21st, 2016 4:00PM