Archived

Avalanche Forecast

Mar 13th, 2015–Mar 14th, 2015

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

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

2: Moderate

The avalanche danger rating in the alpine will be moderate

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: Jasper.

Solar radiation is quite strong whenever there is a break in the clouds. Evaluate sunny slopes carefully after midday.

Weather Forecast

Warm overnight temperatures and high freezing levels are forecast for the next 2 days. Before noon on Saturday, heavy snowfall will begin in the Icefields area with accumulations up to 25cm. This new precipitation will arrive with strong, gusty winds, and cooler temperatures. Warming and clearing should follow the storm on Sunday.

Snowpack Summary

The primary concerns for the snowpack are: 1. Isothermal conditions, especially on solar aspects, 2. Deep persistent weaknesses at the base of the snowpack, and 3. Windslabs in lee Alpine and treeline features. The well settled upper snowpack layers, especially at higher elevations, are bridging lower weaknesses for now.

Avalanche Summary

New avalanche activity is small & restricted to steep solar slopes usually near rocky terrain. Additional inputs of energy from rain, strong solar radiation, & poor refreezing temperatures overnight will exacerbate this problem. Windslabs could be triggered by skiers, and these smaller avalanches could trigger the basal weakness.

Confidence

Intensity of incoming weather systems is uncertain on Saturday

Avalanche Problems

Loose Wet

Warm temperatures and strong solar effect will continue to produce avalanches on steep solar facing terrain.

Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.Avoid steep Southerly aspects.

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

Elevations: All elevations.

Likelihood: Possible

Expected Size: 1 - 3

Wind Slabs

Strong winds at treeline at above have created a new series of windslabs in lee features. Despite warm temperatures, these new windslabs will likely need a few days to bond to older snow surfaces.

Use caution in lee areas. Recent wind loading have created wind slabs.

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

Elevations: Alpine, Treeline.

Likelihood: Unlikely - Possible

Expected Size: 1 - 2

Deep Persistent Slabs

While not reactive recently, the deep persistent weakness could still be triggered by a smaller avalanche or cornice failure.

Consider doing the longer alpine ski tours while the ski penetration remains low.

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

Elevations: All elevations.

Likelihood: Unlikely - Possible

Expected Size: 2 - 4