Archived

Avalanche Forecast

Jan 28th, 2018–Jan 29th, 2018

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

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: Jasper.

Ongoing snowfall will cause the hazard to build through out the day. It might be a good idea to finish your objective early.

Weather Forecast

An Atmospheric River is hitting the South Coast and giving moderate precip as far inland as Jasper. Monday: Snow, 20 cm, High -3 C Low -9 C, light gusting strong SW wind, Freezing level 1700 meters. Tuesday: Flurries, 6 cm, Low -10 C, High -6 C, Light gusting moderate W wind.Wed: Cloudy with sunny periods, Low -16 C, High -10 C, light W wind.

Snowpack Summary

Incoming new snow is building fresh storm slabs and is falling on a persistent slab made up of 3 weak interfaces in the top 30 to 50cm of the snowpack. Depth and distribution of these weak surface hoar/facet layers varies within the terrain; although buried surface hoar has consistently been found in sheltered features at TL.

Avalanche Summary

Avalanche control on Parkers Ridge Friday produced 2 large avalanches, size 2 and 2.5 on a N aspect running as the the persistent slab. On the 18th of 18 shots placed, a large crown appeared up to 1.5m thick x 150m long x 300m wide - interesting display of the variability in sensitivity and spacial distribution of buried weaknesses.

Confidence

Intensity of incoming weather systems is uncertain

Avalanche Problems

Storm Slabs

Incoming new snow and wind will build fresh storm slabs. If triggered these may step down and trigger the persistent weaknesses in the upper snowpack.

The new snow will require several days to settle and stabilize.Minimize overhead exposure during periods of heavy loading from new snow, wind.

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Likely

Expected Size: 1 - 2

Persistent Slabs

This problem is made up of 3 significant interfaces in upper snowpack. Incoming new snow may overload these layers, which have recently been reactive to skier testing and explosive control work, producing a few very significant results.

Carefully evaluate terrain features by digging and testing on adjacent, safe slopes. Avoid steep convexities or areas with a thin or variable snowpack.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 3

Loose Dry

Watch for sluffing in steep terrain.

Be cautious with gully features.

Aspects: All aspects.

Elevations: Alpine.

Likelihood: Likely

Expected Size: 1 - 1.5