Archived

Avalanche Forecast

Feb 28th, 2017–Mar 1st, 2017

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

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

4: High

The avalanche danger rating in the alpine will be high

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: Banff Yoho Kootenay.

Wind, snow and warmer temperatures are expected between today and the end of the week. Expect the danger rating to rise.

Weather Forecast

The forecast region is expecting an increase in wind velocity from the west starting Tuesday evening, accompanied by light snowfall that will carry through until Wednesday morning. Temperatures will slowly rise to the -5 range at valley bottom in the same time period. A second wave of precip will track through the forecast region late on Friday.

Snowpack Summary

There is 15-25 cm of low density snow at tree line with a thin rain-crust below the storm snow at lower elevations. Some wind effect exists in alpine areas and it is expected to increase. Common throughout the region are the weak facets and depth hoar in the lower half of the snowpack, overlain by a 40-60 cm slab of well settled snow.

Avalanche Summary

No new avalanche activity was observed or reported on Tuesday.

Confidence

Timing, track, or intensity of incoming weather system is uncertain on Wednesday

Avalanche Problems

Deep Persistent Slabs

There is a thick slab over a structurally weak snowpack in most areas. Avoid thin parts of a slope or rocky outcrops at tree line and above. A failure can propagate to deeper areas and cause large avalanches.

Use conservative route selection, choose moderate angled and supported terrain with low consequence.Be aware of thin areas that may propogate to deeper instabilites.

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Unlikely - Possible

Expected Size: 2 - 3

Wind Slabs

West wind (mod to strong) and light snowfall amounts will create wind-slabs in lee areas at tree-line and above starting Tuesday evening. There is uncertainty as to how touchy these slabs will be.

Be careful with wind loaded pockets, especially near ridge crests and roll-overs.

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

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 2