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Avalanche Forecast

Jan 27th, 2016–Jan 28th, 2016
Alpine
4: High
The avalanche danger rating in the alpine will be high
Treeline
4: High
The avalanche danger rating at treeline will be high
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
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

Regions: Sea To Sky.

A warm, wet and windy storm will bring the Avalanche Danger to High

Confidence

High

Weather Forecast

Up to 30mm of precipitation is forecast for Wednesday night with another 20cm of snow expected on Thursday. Ridgetop winds will remain extreme from the southwest while freezing levels will drop throughout the day from 2000m to about 1500m. On Friday and Saturday the region will see generally light flurries, significantly decreased winds and freezing levels around 1000m.

Avalanche Summary

In recent days, backcountry avalanche observations have been extremely limited, mostly due to stormy weather. Looking forward, continued warm, wet and windy weather is expected to spark ongoing storm slab activity in high elevation lee terrain, but warm temperatures and loading will also increase the likelihood of waking up any lingering persistent weaknesses that were not triggered by last week's storm.

Snowpack Summary

On Wednesday night and Thursday morning, moderate to heavy snow and strong winds will continue to form deep and dense storm slabs in high elevation terrain and cause substantial cornice growth. At treeline and below, rain is forecast to further saturate the snowpack. In many areas, the early and mid-January surface hoar layers have been wiped-out by last week's storm and subsequent avalanche cycle; however, "sudden" test results and isolated persistent slab avalanches prove these interfaces should remain on your radar. These layers would be down between 80 and 150 cm deep, and still have the capacity to surprise with nasty consequences. The mid and lower snowpack is generally strong, with the exception of shallower snowpack areas that may be more faceted.

Avalanche Problems

Storm Slabs

Heavy snowfall and extreme winds on Wednesday and Thursday morning will form deep and dense storm slabs at higher elevations. Watch for increased triggering in wind-exposed terrain.
Be alert to conditions that change with elevation.>Stay off recent wind loaded areas until the slope has had a chance to stabilize.>Avoid all avalanche terrain during periods of heavy loading from new snow, wind, or rain.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Likely - Very Likely

Expected Size: 1 - 4

Persistent Slabs

There are still areas where last week's storm and subsequent avalanche cycle did NOT destroy buried surface crystals. In these areas, loading from rain and snow will continue to stress these layers with the potential for large, destructive avalanches
Be aware of the potential for large, deep avalanches due to the presence of buried surface hoar.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 3 - 5

Cornices

Recent storms have formed very large and unsupported cornices, and at least one person has taken an unexpected ride. Use extra caution around ridge crests in the alpine.
Give cornices a wide berth when travelling on or below ridges.>

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

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 3