Archived

Avalanche Forecast

Apr 6th, 2017–Apr 7th, 2017

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

3: Considerable

The avalanche danger rating below treeline will be considerable

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

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: Little Yoho.

Another warm day Friday before we see a cooling trend through the weekend. Travel at treeline and below will not be great over the next few days.

Weather Forecast

A series of warm low pressure systems continue to move across BC and AB. Showers and flurries forecasted for Thursday evening followed by freezing levels dipping down to 1600 m. Friday it will be cloudy and warm with more precipitation in the evening. Expect rain in the valley bottom and snow above 2000m may accumulate 10cm before it stops.

Snowpack Summary

A settled, mostly dry snowpack exists on shaded aspects above 2300m. On other aspects and below 2300m, expect morning crust and wet snow by mid-day. Concern remains about the integrity of the deeper snowpack; avoidance of large slopes is still recommended. Warmth over the next few days will release cornices and slush avalanches at lower elevations.

Avalanche Summary

Several cornice triggered deep slab avalanches have been observed on the Wapta over the past few days,

Confidence

Avalanche Problems

Cornices

April is cornice season, and we are getting regular reports of cornices failing. Mature cornices can propagate much further than you expect, so give them a wide margin when traveling on ridges and get up early and hurry if you must travel below them.

Avoid travel on slopes that are exposed to cornices overhead.

Aspects: North, North East, East.

Elevations: Alpine.

Likelihood: Possible - Likely

Expected Size: 1 - 2

Persistent Slabs

Persistent weak layers deep in the snowpack continue to cause uncertainty, despite the surface layers being remarkably strong. Continue to avoid exposure to large slopes. Patience is a virtue as we wait for a melt/freeze cycle to change anything.

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Possible

Expected Size: 2 - 4

Loose Wet

Wet snow flows like water in gullies during warm spring days, and the next few days we expect wet snow avalanches to be common in gully areas at and below treeline. Ice climbers - avoid steep low elevation gullies.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Unlikely - Possible

Expected Size: 1 - 2