Archived

Avalanche Forecast

Mar 12th, 2014–Mar 13th, 2014

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

3: Considerable

The avalanche danger rating below treeline will be considerable

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

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: Glacier.

Get out the door early and be clear of solar-affected slopes before it warms up. The March sun packs a punch these days!

Weather Forecast

The biggest weather factor today is the strong sun that will hit slopes early, causing a rapid warm-up and freezing levels to rise to 1900m. Winds will be light with occasional moderate gusts from the SW. A weak disturbance floats through the area overnight, dusting us with trace amounts of snow and lowering freezing levels to valley bottom.

Snowpack Summary

Rain crust below 1700m on the surface. Above tree line the snow is generally wind affected, but pockets of undisturbed powder do exist in the alpine. The heavy over light snow has settled out, hence, travel has eased. March 2nd crust is down around 1m. The Feb10 surface hoar/crust interface is down 1.5-2m. The mid to lower snowpack is well settled.

Avalanche Summary

With the solar input and warm valley temp's we saw plenty of activity from steeper start zones in the highway corridor. Numerous slides from size 2 to 3.5 were observed, with moist debris in the deposits. Nearby operations are reporting many skier accidental and remote avalanches failing in the storm snow or deeper on the buried weak layers.

Confidence

The weather pattern is stable

Avalanche Problems

Wind Slabs

The recent wind slabs from the latest storm are settling out, but they will be stressed by today's sun and rapid warming. The first couple of hours of intense sun will likely bring activity to this layer.

Make your travel plans to take advantage of overnight freezing.Plan to be off big slopes before the temperatures rises and the snowpack deteriorates.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 3

Cornices

Cornices will also feel a little heavier today with sun and warming. Give them a wide berth. A party of 4 nearly went tumbling off Castor Peak's west ridge when they triggered a cornice that they were standing on.

Give cornices a wide berth when travelling on or below ridges.

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

Elevations: Alpine.

Likelihood: Possible

Expected Size: 1 - 3

Persistent Slabs

There are two layers of concern. The first is a sun crust on S-SW slopes, buried ~1m deep. The second is the Feb 10 surface hoar/facet complex, down 1.5-2m. Both exhibit sudden failures, meaning there is potential for wide propagation.

Be aware of the potential for large, deep avalanches due to the presence of buried surface hoar.Be aware of thin areas that may propogate to deeper instabilites.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Unlikely - Possible

Expected Size: 3 - 4