Archived

Avalanche Forecast

Jan 11th, 2018–Jan 12th, 2018

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

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

1: Low

The avalanche danger rating below treeline will be low

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.

If Friday night's storm arrives early, the avalanche danger may be higher than posted.

Confidence

Moderate - Timing of incoming weather systems is uncertain on Friday

Weather Forecast

Friday: About 5cm of the new snow with an additional 10-15cm overnight / Moderate southwest winds / Freezing level at 600mSaturday: Mix of sun and cloud / Light southwest winds / Freezing level at 1400mSunday: Mostly clear skies / Light southwest winds / Freezing level at 2300m

Avalanche Summary

On Wednesday the upper snowpack was largely unaffected by explosives control work, but it did produce a few storm slab avalanches to size 1. Ski cutting in the region also produced similar avalanche activity in isolated terrain.

Snowpack Summary

10 to 15 cm of light density snow from Monday night and Tuesday now rests on 20 to 30 cm of slightly heavier snow that fell over the weekend. This snow was redistributed by moderate to strong southeast through southwest winds on Sunday. All of this snow is above the the January 6th crust which is present to at least 2100 m, maybe higher. This crust is reportedly breakable below 2100 m. Below the crust there is about 20 cm of settled moist snow.Up to 100 cm below the surface there is a widespread melt-freeze crust that was buried on December 15th, but this layer has not produced any recent avalanche activity and is trending towards dormancy. Beneath the mid-December crust, the lower snowpack is generally strong and well settled.

Avalanche Problems

Storm Slabs

New snow and wind on Friday afternoon is expected to promote new storm slab development and increase the avalanche danger at the end of the day. If the new snow arrives early, the avalanche danger may be higher than posted.

Be alert to conditions that change with elevation and time of day.Be cautious in lee features above treeline, old wind slabs rest on a buried crust.Watch for fresh storm slabs building throughout the day.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible - Likely

Expected Size: 1 - 2