Archived

Avalanche Forecast

Jan 23rd, 2020–Jan 24th, 2020

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

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

1: Low

The avalanche danger rating at treeline will be low

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Regions: Lizard-Flathead.

Strong southwesterly winds will continue to form reactive wind slabs Friday. Be especially cautious of natural overhead hazard and human triggering of wind loaded features.

Confidence

Moderate - Uncertainty is due to the speed, direction, or duration of the wind and its effect on the snowpack.

Weather Forecast

Thursday night: Around 5 cm new snow. Moderate southwesterly winds. Freezing level around 1600 m.

Friday: Around 10-15 cm new snow. Moderate southwesterly winds. Freezing level around 1500 m.

Saturday: Up to 5 cm new snow. Light southwesterly winds. Freezing level around 1400 m.

Sunday: Flurries. Light southwesterly winds. Freezing level around 1400 m.

Avalanche Summary

Over the last 2 days there have been reports of natural storm slab activity up to size 2 on northeast aspects at alpine and treeline elevations. Explosive control work has been up to size 2, as well as reports of skier triggered size 1s.

Snowpack Summary

New snow and moderate winds have formed soft wind slabs in lee features in the alpine and treeline.

The stout upper snowpack continues to settle in mild temperatures. Several crust layers exist in the mid snowpack as a result of previous warming and rain events. These have not been identified as bed surfaces or failure planes in recent avalanche activity.

The bottom 10-20 cm of the snowpack consists of faceted snow and decomposing crusts. Although inherently weak, this basal layer has not been an active avalanche problem in our region since 2019.

Terrain and Travel

Be alert to conditions that change with elevation, aspect and exposure to wind.
Avoid freshly wind loaded terrain features.
Pay attention to cornices and give them a wide berth when traveling on or below ridges.

Avalanche Problems

Wind Slabs

Strong southwesterly winds continue to form reactive wind slabs. Expect possible natural activity and likely human triggering in the alpine.

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

Elevations: Alpine, Treeline.

Likelihood: Likely

Expected Size: 1 - 2