Archived

Avalanche Forecast

Jan 16th, 2025–Jan 17th, 2025

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: Banff, Banff Yoho Kootenay, East Side 93N, Field, Kootenay, LLSA, Lake Louise, Sunshine, West Side 93N.

Mt. Bosworth avalanche closure zone is CLOSED on Thursday, January 16th.

High elevation winds have been strong to extreme for the last week, so be on the lookout for windslabs if venturing into high, windy spots.

Deep slabs haven't been observed in days, but a weak snowpack persists in shallow areas - ski the thick, avoid the thin.

Confidence

Moderate

Avalanche Summary

One size 1.5 windslab on an alpine SE aspect on Bow Peak. Thursday morning, size 2 wind triggered slab and loose dry avalanches were observed in Little Yoho on Mt. Stephen and Mount Field.

Snowpack Summary

Eventhough the alpine has been previously scoured by wind, Strong to extreme S-SW winds Wednesday night and Thursday created fresh wind slabs. Generally, at treeline, there is 10-20 cm soft surface snow in wind-sheltered areas overlying a mid-pack of weak facets, over the breaking down October crust and depth hoar at the bottom. An average of 60-100cm of snow can be found at treeline elevations.

Weather Summary

Thursday, we expect extreme SW winds accompanied by up to 5 cm new snow.

On Friday, we will see cooling temperatures and easing winds as arctic air moves in for the weekend.

Terrain and Travel Advice

Watch for newly formed and reactive wind slabs as you transition into wind-affected terrain.
Wind slabs are most reactive during their formation.

Avalanche Problems

Wind Slabs

Strong to extreme winds with light flurries creating fresh reactive windslabs.

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

Elevations: Alpine, Treeline.

Likelihood: Likely

Expected Size: 1 - 2

Loose Dry

Strong to extreme winds Thursday will trigger loose dry avalanches in steep terrain, including couloirs and ice-climbing areas.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 2

Deep Persistent Slabs

Weak facets exist at the base of the snowpack. Although we haven't seen much avalanche activity on this layer in a while, the snowpack structure is weak and large open slopes at treeline and in the alpine remain suspect.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Unlikely

Expected Size: 1.5 - 3