Archived

Avalanche Forecast

Feb 29th, 2016–Mar 1st, 2016

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

4: High

The avalanche danger rating in the alpine will be high

Treeline

3: Considerable

The avalanche danger rating at treeline will be considerable

Below Treeline

3: Considerable

The avalanche danger rating below treeline will be considerable

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

Regions: Sea To Sky.

Strong winds will probably make the alpine an unpleasant place to be on Tuesday. Watch out for overhead exposure if you end up hiding out at treeline. Natural avalanches will become increasingly likely through the day.

Confidence

High - Due to the number and quality of field observations on Tuesday

Weather Forecast

A necessary reset is on its way, were entering a prolonged period of cold, wet storm systems. TUESDAY: light snow overnight becoming heavy through the day with accumulations of 20-30cm expected, moderate to strong southerly winds 1500m freezing level. WEDNESDAY: heavy snow continues overnight with another 10-20cm expected before the snow stops in the morning, light southwesterly winds, 1500m freezing level. THURSDAY light to moderate snow with moderate southwest winds, 1500m freezing level.

Avalanche Summary

A couple of new size 1-2 wind slabs were triggered naturally and by skiers over the weekend. Cornices large and fragile. They have been reported to be failing naturally and would likely collapse under the weight of a person. I suspect that we will see a widespread avalanche cycle through the storm on Tuesday as the new snow adds load to a variety of untested old surfaces.

Snowpack Summary

New snow and strong winds are going to continue to build fresh soft slabs in the alpine and at treeline. The upper snow pack sits on a widespread crust at treeline and below as well as up to an elevation of about 2200m on aspects that see direct sun. In isolated sheltered north aspects it may sit on pockets of surface hoar or facets. Cornices are large and weak. The midpack is generally well settled.

Avalanche Problems

Storm Slabs

Heavy snow and wind will trigger a natural avalanche cycle. Human triggered avalanche will become increasing likely on steep unsupported slopes or in wind loaded features through the day.

Avoid steep, open slopes.>Minimize overhead exposure; avalanches triggered by windloading may reach run out zones.>Be careful with wind loaded pockets>

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Likely - Very Likely

Expected Size: 1 - 3