Archived

Avalanche Forecast

Jan 18th, 2014–Jan 19th, 2014

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

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

2: Moderate

The avalanche danger rating below treeline will be moderate

Regions: Northwest Inland.

Confidence

Poor

Weather Forecast

A strong upper ridge of high pressure will dominate the weather pattern for a week or more. However, a weakening Pacific front will move through the ridge Saturday resulting in light precipitation through Saturday evening.Saturday Night: Freezing Level: 1100m; Precip: 1/3mm 2/6cm Wind: Strong, WSunday: Freezing Level: 800m; Precip: Nil; Wind: Decreasing throughout the day.Monday: Freezing Level: Inverted, below freezing at Valley Bottom, above freezing from 1200 2600m Precip: Trace; Wind: Mod, SWTuesday: Freezing Level: Inverted, below freezing at Valley Bottom, above freezing from 1200 2600m Precip: Nil; Wind: Mod, SW

Avalanche Summary

A large avalanche cycle that was most active in the northern portion of the region wrapped up January 15th. All aspects and elevations were involved with natural avalanches running to size 3.5. Most of these avalanches likely ran on the early January surface hoar layer. In the Southern portion of the region a few small slab avalanches were reported from steep leeward terrain.

Snowpack Summary

Previously strong winds have resulted in widespread wind damaged/loaded snow at and above treeline. The buried surface hoar layer at treeline and the basal facets in thin rocky areas at treeline and in the alpine remains a concern.

Avalanche Problems

Wind Slabs

New snow and wind will likely set up reactive slabs, especially in lee and cross-loaded terrain in the alpine.

Watch for whumpfing, hollow sounds, shooting cracks or recent avalanches.>Avoid freshly wind loaded features.>

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

Elevations: All elevations.

Likelihood: Possible - Likely

Expected Size: 1 - 3

Deep Persistent Slabs

A weak layer of facets/depth hoar at the base of the snowpack has been responsible for some recent very large avalanches. The likelihood of triggering this layer is now considerably reduced, but the consequences associated with this layer are huge.

Minimize exposure to overhead avalanche terrain, large avalanches may reach run out zones.>Be aware of the potential for large, deep avalanches.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 5