Avalog Join
Archived

Avalanche Forecast

Dec 29th, 2014–Dec 30th, 2014
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
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
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: Purcells.

Avalanche danger is expected to remain at Considerable during the forecast cold and clear weather for the end of the year.

Confidence

Fair

Weather Forecast

Clear and cold overnight with alpine temperatures dropping to about -25 and moderate Northeast winds. Winds becoming light Northwest during the day on Tuesday and alpine temperatures rising up to about -14 under clear skies. Cold and clear with light Westerly winds on Wednesday. Increasing cloud on Thursday afternoon with a chance of light snow in the evening.

Avalanche Summary

No natural avalanches reported. Explosives control work resulted in avalanches up to size 1.5 that appear to have run on the mid-December surface hoar that is buried down 40-60 cm.

Snowpack Summary

Some areas may have a thin layer of surface hoar that was buried on December 27th and now has about 5-10 cm of light dry snow above. The slab above the persistent weak layer of surface hoar and crust that was buried in mid-December is now 40-60 cm thick and gives mostly sudden planar results in snow profile tests when moderate forces are applied. The persistent slab problem is widespread across the region and is not expected to improve it's bonding properties during the forecast dry and cold weather. Shallow snowpack areas continue to have concerns for a deeper early season crust/facet layer down more than a metre that may collapse under large loads or from weak trigger spots around exposed rocks and/or trees.

Avalanche Problems

Persistent Slabs

Thin windslabs and recent storm slabs may be sitting on a weak layer of surface hoar and/or a crust. This problem may persist through the Holiday season.
Use conservative route selection, dig down and test weak layers before committing to anything. >Stick to simple terrain, small features with limited consequence and be aware of what is above you at all times.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Likely

Expected Size: 1 - 4

Deep Persistent Slabs

Shallow snowpack areas may continue to have concerns for deeply buried crusts with facets at the interface.  Large triggers like storm slab avalanches in motion may step down to near the ground where this problem exists.
Conditions may be worse in the north of the region, so get to know your local snowpack.>Be aware of thin areas that may propogate to deeper instabilites.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Unlikely

Expected Size: 3 - 6