Archived

Avalanche Forecast

Apr 10th, 2014–Apr 11th, 2014

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

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

1: Low

The avalanche danger rating below treeline will be low

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

1: Low

The avalanche danger rating below treeline will be low

Regions: Glacier.

Start early. Start early. Start early. Avoid the warmer times of the day when the surface crusts have softened.

Weather Forecast

Rogers Pass will see a mix of sun and cloud with the occasional flurry today. Freezing levels may rise to 1600m, but it will remain cool in the alpine and tree-line elevations. Winds will be light to moderate from the SW.

Snowpack Summary

A good freeze has left the surface snow crusty at lower elevations, although some dry snow may be found on due north aspects above 2400m. Extreme winds may have blown this into slabs in exposed lee areas. The mid to lower snowpack is very well settled. If the sun pops through, expect a rapid deterioration of low elevation surface crusts.

Avalanche Summary

Yesterday, several natural avalanches from size 1.5-2.5 were noted from solar aspects. These occurred mainly in the afternoon at the warmest time of day. A notable size 3.5 occurred at the peak of the warmth 36 hours ago on a SW aspect, showing that the persistent weak layers are still active once the snowpack warms up enough.

Confidence

Avalanche Problems

Storm Slabs

There may be lingering surface slabs at alpine and tree-line elevations, due to the strong winds accompanying the last snowfall.

Use caution in lee areas. Recent wind loading have created wind slabs.If triggered the wind slabs may step down to deeper layers resulting in large avalanches.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 2

Loose Wet

If the sun comes out for prolonged periods today, we will likely see a rapid deterioration of the surface crusts. Start early if you are exposed to solar aspects, especially at lower elevations.

Avoid slopes with glide cracks.Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.

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

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 3

Persistent Slabs

The large size 3.5 from Moccasin Flats 36 hours ago shows the persistent slabs have not gone away. Larger triggers, like cornices or surface avalanches, may step down to deeper layers.

If triggered the storm slabs may step down to deeper layers resulting in large avalanches.Be aware of the potential for full depth avalanches due to deeply buried weak layers.

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

Elevations: All elevations.

Likelihood: Unlikely - Possible

Expected Size: 2 - 4