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

Avalanche Forecast

Dec 5th, 2011–Dec 6th, 2011
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
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: Northwest Coastal.

Confidence

Fair - Due to limited field observationsfor the entire period

Weather Forecast

Tuesday: Winds are expected to veer to northwesterlies and ease to moderate in the wake of Monday's frontal system. The temperature inversion is also expected to dissipate with freezing levels returning to valley bottoms. Wednesday and Thursday: The ridge of high pressure is expected to rebuild with a dry outflow pattern.

Avalanche Summary

Recent explosives control produced isolated wind slab avalanches up to Size 2.5 generally on easterly aspects. A few deep slab avalanches up to Size 4 were explosive-triggered in Bear Pass. Many of these involved the entire 200-300cm snowpack running on summer firn in extreme terrain. Full depth glide avalanches have also been running below treeline in the southwestern part of the region.

Snowpack Summary

Hard and soft wind slabs formed by recent moderate to strong westerly winds are lurking on isolated lee features in treeline and alpine areas. Warm temperatures and sun-exposure, and subsequent freezing, formed a surface crust especially on southerly aspects. New surface hoar growth was observed on shady aspects at and below treeline. Surface hoar buried at the end of last week was observed down 20-40 cm in sheltered treeline areas. Widespread glide cracks have opened up in some areas.

Avalanche Problems

Wind Slabs

Hard and soft wind slabs are lurking in exposed terrain on a variety of aspects well into treeline.

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

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 2 - 4