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

Avalanche Forecast

Dec 22nd, 2014–Dec 23rd, 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
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

Regions: Northwest Inland.

This forecast was created using limited field data.  If you are out in the mountains, please consider sending us your observations or posting on our new website.

Confidence

Poor - Due to the number of field observations

Weather Forecast

A frontal system is expected to bring around 10-15mm of precipitation to the North Coast inland on Tuesday. Another 5-10mm is possible Tuesday night into Wednesday morning. Freezing levels on Tuesday are expected to be 800-1000m with strong-to-extreme winds from the SW in the alpine. On Wednesday, precipitation should taper off in the morning with freezing levels around 500m and winds easing to moderate NW in the alpine. Christmas day looks to be a mix of sun and clouds with freezing levels near valley bottom and moderate winds in the alpine.

Avalanche Summary

We received a report on Sunday from the Hankin area of a natural size 1 slab avalanche.  This occurred on a north aspect at treeline. The crown depth was around 20cm and it failed on the most recent rain crust.  Check out the report here: https://goo.gl/WdmvxL

Snowpack Summary

The weekend storm slab is between 20-40 cm deep. Very strong winds have transported snow in the alpine and at treeline into pockets of windslab that may not be well bonded to the old surfaces. Below the new snow you'll likely find wind-scoured surfaces and old wind slabs in exposed terrain, and settled storm snow closer to treeline. Near the base of the snowpack, weaknesses such as the mid-November crust-facet layer are still of concern. I'd use extra caution around steep, unsupported high elevation terrain as avalanches at this interface could propagate over wide distances.

Avalanche Problems

Storm Slabs

The new storm snow is adding to the storm loading from the weekend. Strong winds are loading leeward slopes in exposed terrain.
Avoid freshly wind loaded features.>The new snow will require several days to settle and stabilize.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Likely

Expected Size: 1 - 3

Deep Persistent Slabs

Deeply buried weak layers may release during periods of high loading from new snow and wind. Triggering of these deep layers is most likely from shallow snowpack areas such as areas around rock outcrops.
Avoid convexities or areas with a thin or variable snowpack.>Be aware of thin areas that may propogate to deeper instabilites.>

Aspects: All aspects.

Elevations: Alpine.

Likelihood: Unlikely - Possible

Expected Size: 2 - 4