Banff Yoho & Kootenay National Park Avalanche Forecast

Issued: Feb 13th, 2021 4:00PM

Sat Feb 13th Current Conditions
Alpine Moderate Treeline Moderate Below Treeline Low
Sun Feb 14th 2 Day Outlook
Alpine Moderate Treeline Moderate Below Treeline Low
Mon Feb 15th 3 Day Outlook
Alpine Moderate Treeline Moderate Below Treeline Low

The alpine rating is moderate, the treeline rating is moderate, and the below treeline rating is low. Known problems include Wind Slabs, Persistent Slabs and Loose Dry.

New wind slabs have been observed over the last 24 hours as well as cornice failures. We have added a persistent layer mainly for the Kootenay region as we keep getting isolated reports including Saturday.

Summary

Weather Forecast

After another -25 to -30C morning, temperatures will rise again on Sunday with highs at treeline of between -12 to -16 C. Skies will remain mainly clear. Alpine winds will decrease to light and will switch to a more Westerly flow. We will see a gradual increase in temperature over the next week.

Snowpack Summary

Winds have created small slabs in lee areas of the alpine, and wind effect in open alpine and treeline areas. The surface snow is facetting quickly and beginning to sluff more easily in steep terrain. A facet layer from Jan 27th is present at treeline and in the alpine down 30-40cm. On steep south this layer may consist of a thin sun crust as well.

Avalanche Summary

Increased winds saw some loose dry activity in steep alpine terrain. Cornice failures have been observed over the past few days including one on Fatigue Mountain today that triggered a size 3 on the ground reminding us that there is still a deep layer. Forecasters ski cut a size 2 in the Simpson area at 2100 m on the persistent layer that ran 450m.

Confidence

Due to the number and quality of field observations

Problems

Wind Slabs

An icon showing Wind Slabs

Likelihood

Possible

Expected Size

1 - 2

New wind slabs have been reported from increased winds over the last 24 hours that are generally small in size but would be of concern in steep, alpine terrain. Winds have also formed cornices that have been seen to fail and trigger wind slabs below.

  • Use caution in lee areas. Recent wind loading has created wind slabs.

Aspects:

All aspects.

Elevations:

Alpine.

Persistent Slabs

An icon showing Persistent Slabs

Likelihood

Possible

Expected Size

1 - 2

We are adding this after a week of isolated observations. It exists mainly in the Kootenay region but there is some uncertainty around this. It is failing on average 40cm deep on the Jan. 27 layer of facets, or facets/thin suncrust on steep South.

Aspects:

All aspects.

Elevations:

Alpine, Treeline.

Loose Dry

An icon showing Loose Dry

Likelihood

Possible

Expected Size

1 - 1.5

As the surface snow facets and weakens, it is starting to sluff more easily in steep terrain. This is mostly a problem in narrow confined terrain like gullies or couloirs.

  • On steep slopes, pull over periodically or cut into a new line to manage sluffing.
  • Be careful of loose dry power sluffing in steep terrain.

Aspects:

All aspects.

Elevations:

Alpine, Treeline.

Valid until: Feb 14th, 2021 4:00PM

Forecast Trend

The latest forecast danger ratings, broken down to elevation. See how an elevation is trending.