Archived

Avalanche Forecast

Nov 25th, 2018–Nov 26th, 2018

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

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: South Columbia.

A warm and wet system is moving across the province. Snowfall and rising temperatures will test the strength of buried layers within the snowpack. In areas with higher than forecasted snowfall, avalanche hazard may be higher than forecasted.

Confidence

Low - Intensity of incoming weather systems is uncertain

Weather Forecast

SUNDAY NIGHT: Mainly cloudy with isolated flurries / Precipitation: up to 5cm / Light south-southwest ridge windMONDAY: Flurries / Accumulation: 5-15 cm / Alpine temperature: Low -4C / Moderate south ridge wind / Freezing level 1400mTUESDAY: Periods of snow / Accumulation: 10-25 cm / Alpine temperature: High 0C / Moderate south-southwest ridge wind / Freezing level 1700mWEDNESDAY: Cloudy with flurries / Accumulation: up to 10 cm / Alpine temperature: High -3C / Light to moderate south-southwest ridge wind / Freezing level 1400m

Avalanche Summary

On Saturday, a large human triggered avalanche was reported on Meadow Mountain. The size 3 avalanche occurred on a steep, north aspect in the alpine and failed to ground, likely on a crust buried in October. Find the MIN report here.Earlier in the month, a natural avalanche cycle took place over the late October crust/facet combination. Be aware of the continued possibility for smaller avalanches to 'step down' or even initiate at this deeper layer. It exists primarily in the alpine.

Snowpack Summary

15-30 cm of recent snow covers two surface hoar layers (weak feathery snow), down about 30 and 60 cm respectively. Near the ground, faceted/sugary snow on a crust supports the snowpack. The total snowpack depth varies from 110-160 cm in the alpine, with snowpack depth decreasing quickly with decreasing elevation.

Avalanche Problems

Storm Slabs

Slabs may be more reactive in wind-exposed terrain and areas where the new snow has a weak bond with the underlying surface layer.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Unlikely - Possible

Expected Size: 1 - 2.5

Deep Persistent Slabs

A buried weak layer exists at the base of the snowpack in the alpine. This weak layer has already produced large avalanches and may be triggered by the weight of a person.

Caution in lee and cross-loaded terrain near ridge crests.Be aware of thin areas that may propogate to deeper instabilites.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Unlikely - Possible

Expected Size: 1.5 - 3