Register
Get forecast notifications
Create an account to receive email notifications when forecasts are published.
Login
Archived

Avalanche Forecast

Feb 3rd, 2012–Feb 5th, 2012
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
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
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: Northwest Coastal.

Warm temperatures in alpine areas could cause large, unexpected avalanches, especially on south-facing slopes.

Confidence

Fair - Freezing levels are uncertain

Weather Forecast

Saturday and Sunday: Dry or very light flurries, with alpine temperatures around -2C. Winds expected to be light southwesterly rising to moderate southeasterly. Monday: Clear with sunny spells. Temperatures below freezing at low elevations but alpine areas may see inversion conditions that will elevate temperatures to near zero.

Avalanche Summary

On Friday, slab avalanches up to size 3.5 were reported in response initially to rain and then during the day to intense solar radiation. On Thursday, numerous large (up to size 3) slab avalanches were reported out of lee terrain (SW predominantly) along Bear Pass during the warming period as the snow turned to rain. Lower elevations were especially active.

Snowpack Summary

Total snowpack depths pushing 5m at treeline are at new record levels for this time of year. Recent warm temperatures helped settle storm snow into a touchy surface slab at lower elevations. Other weaknesses can be found within the upper snowpack and the Jan. 20th facets down around 150cm. These create the potential for large step-down avalanches, but things seem to be settling rapidly. Strong winds associated with recent storms means large weak wind slabs and cornices on lee and cross-loaded terrain. Most snowpack concerns are limited to the surface layers. However, large triggers such as cornice falls and smaller avalanches stepping-down could affect deeper weaknesses.

Avalanche Problems

Storm Slabs

Recent rain and warm temperatures have promoted avalanche activity on storm slabs. Alpine temperatures are expected to remain high and this problem is expected to continue through the forecast period.

Aspects: All aspects.

Elevations: Alpine.

Likelihood: Likely

Expected Size: 3 - 7

Persistent Slabs

Rain and warm temperatures have promoted recent avalanche activity at low elevations that has run on a layer of facets buried around 20-Jan. This problem may creep higher in elevation with continued warm alpine temperatures.

Aspects: North, North East, East.

Elevations: All elevations.

Likelihood: Likely

Expected Size: 2 - 6

Cornices

Cornices are expected to become weak with continued warm temperatures and solar radiation.

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

Elevations: Alpine.

Likelihood: Possible - Likely

Expected Size: 3 - 7