Archived

Avalanche Forecast

Nov 28th, 2016–Nov 29th, 2016

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

1: Low

The avalanche danger rating at treeline will be low

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

1: Low

The avalanche danger rating at treeline will be low

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Regions: South Columbia.

Recently formed storm slabs may still be reactive to human triggers. Use additional caution in shallow, rocky, or wind affected alpine terrain.

Confidence

Low - Due to the number of field observations

Weather Forecast

Tuesday: Mix of sun and cloud / light southerly winds / Freezing level around 900m. Wednesday: Possible flurries / Light westerly winds / Freezing level around 1200m. Thursday: Mix of sun and cloud / Light northwesterly winds / Freezing level around 900m.

Avalanche Summary

No new avalanches were reported in this region on Sunday. However, a natural size 3 and several size 2 avalanches were reported on the east side of Rogers Pass in the highway corridor.

Snowpack Summary

30-70 cm of recent snow formed storm and wind slabs that were reactive to human triggers over the weekend. These slabs will likely become less reactive in the coming days but will still require careful slope by slope evaluation. Reports suggest the the mid-November crust down 60-120 cm is well bonded to the overlying snow. Below the crust the snowpack is generally well settled. Limited observations suggest snowpack depths vary greatly throughout the region and are on average 100-180 cm at treeline elevations with generally less snow in the southern portion of the region.

Avalanche Problems

Wind Slabs

Recently formed wind slabs may remain reactive to human triggers for several days.

Be cautious as you transition into wind affected terrain.Travel on ridgetops to avoid wind slabs on slopes below.Avoid slopes that sound hollow or drum-like.

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

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 2

Storm Slabs

Storm slabs may remain touchy even though the storms have passed, especially at higher elevations and on wind-loaded features.

Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.If you are increasing your exposure to avalanche terrain, do it gradually as you gather information.Avoid regrouping in runout zones.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 2 - 3