Archived

Avalanche Forecast

Feb 17th, 2018–Feb 18th, 2018

Alpine

3: Considerable

The avalanche danger rating in the alpine will be considerable

Treeline

3: Considerable

The avalanche danger rating at treeline will be considerable

Below Treeline

2: Moderate

The avalanche danger rating below treeline will be moderate

Alpine

3: Considerable

The avalanche danger rating in the alpine will be considerable

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

2: Moderate

The avalanche danger rating below treeline will be moderate

Alpine

3: Considerable

The avalanche danger rating in the alpine will be considerable

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

2: Moderate

The avalanche danger rating below treeline will be moderate

Regions: Glacier.

Previous winds have created pockets of wind slab in the Alpine and at treeline. Keep a heads up as you transition into these areas.

Weather Forecast

A weak low pressure system brings scattered flurries to our region today. We could see 5-10cms of accumulation. Temperatures will remain cool with an alpine high of -13.0 and light ridgetop winds occasionally gusting to 35km/h. On Sunday, cold arctic air moves into our region with temperatures dropping into the minus 20s.

Snowpack Summary

Storm snow remains unsettled with up to 50cm of ski penetration. Ongoing southerly winds have created reactive pockets of wind slab in exposed areas. On solar aspects, a well developed crust is buried 40cm. Persistent weak layers from January and December are now buried 150-200cm.

Avalanche Summary

Natural avalanche activity tapered slightly yesterday. On Thursday a hand-full of natural avalanches were observed to size 3 in the highway corridor, most were in steep un-ridable North facing terrain. Also size 2.5 was reported in Connaught drainage in the Cheops North 1 slide path that ran to the valley bottom, nearly hitting the skin track.

Confidence

Intensity of incoming weather systems is uncertain

Avalanche Problems

Storm Slabs

Natural and skier triggered avalanches are still resulting from this reactive storm slab problem. Loading from moderate to strong southerly winds has increased the likelihood storm slabs being triggered and propagating, especially in exposed areas.

If triggered the storm slabs may step down to deeper layers resulting in large avalanches.Use caution in lee areas in the alpine and treeline. Storm snow is forming reactive slabs.

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Likely

Expected Size: 1.5 - 2.5

Persistent Slabs

These slabs will be most susceptible to triggering in shallow areas. This type of instability will linger for a while yet. The significant storms seen recently have overloaded these layers, priming slopes to fail only awaiting a trigger.

Be aware of the potential for large avalanches due to the presence of buried surface hoar.Avoid thin, rocky or unsupported slopes.

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Possible

Expected Size: 2 - 4