Avalanche Forecast

Issued: Nov 17th, 2015 8:27AM

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

Parks Canada andrew jones, Parks Canada

We are in the middle of a storm with dangerous avalanche conditions. Ongoing wind and precipitation will cause stability to deteriorate throughout the day.

Summary

Weather Forecast

Heavy precipitation expected for today with snow fall amounts up to 40cm by this evening. Strong SW winds gusting to extreme near ridge top. Freezing levels rise to 1450m this afternoon with alpine temperatures reaching a daytime high of -5. A northwesterly flow will follow the passing of the storm this evening bringing dry and cold conditions

Snowpack Summary

25cm of new, unconsolidated snow fell overnight. Strong S-SW winds accompanied the snow fall and heavily loaded lee features and aspects, forming deeper slabs. New snow overlies a crust below 1700m. The November 11 surface hoar layer is present above 1800m with localized distribution. An isolated basal weakness is capable of large slides.

Avalanche Summary

Several avalanches from steep terrain were observed in the highway corridor, running up to size 2.5 with moist debris terminating halfway through their run-out zones.

Confidence

Intensity of incoming weather systems is uncertain

Problems

Storm Slabs

An icon showing Storm Slabs
Last night's snow fell under strong SW winds creating heavy loading in localized areas. Ongoing wind and snow will intensify this problem today. Storm slabs will be easily triggered today and have the potential to run to the end of avalanche paths.
Avoid avalanche terrain during periods of heavy loading from new snow and wind.Minimize exposure to overhead avalanche terrain, large avalanches may reach run out zones.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

1 - 3

Loose Dry

An icon showing Loose Dry
New snow will be sluffing from steep terrain. These avalanches can be particularity hazardous around terrain traps, especially with early season hazards like rocks and trees.
Be cautious of sluffing in steep terrain.Sluffs may trigger deeper instabilities.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Very Likely

Expected Size

1 - 2

Deep Persistent Slabs

An icon showing Deep Persistent Slabs
Recent natural avalanches have been triggered on this layer. New storm snow and strong winds will be capable of releasing large avalanches on this layer. These avalanches can easily reach the end of run out zones.
If triggered the storm slabs may step down to deeper layers resulting in large avalanches.Avoid exposure to overhead avalanche terrain, large avalanches may reach the end of run out zones.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

2 - 4

Valid until: Nov 18th, 2015 8:00AM