Avalanche Forecast

Issued: Mar 6th, 2019 4:00PM

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

stephen holeczi, Parks Canada

Banff Yoho Kootenay.

A few cm Thursday won't do much to change the bulletin. Watch locally for an early increase in alpine wind speeds which could trigger some loose dry avalanches at ridgetop. Good ski quality still, but valley bottoms are a bit rugged.

Summary

Weather Forecast

Overnight lows around -12C and highs just below freezing for Thursday.Â Winds will increase later in the afternoon and switch to SW.Â There will be increasing cloud and a few cm over the day, and a few more Friday.Â 3000m temperatures will cool off tomorrow afternoon and will be back to -20C on Friday.Â

Snowpack Summary

Prolonged cold temperatures have weakened and facetted the upper snowpack. Wind effect is common in the alpine and several recent crusts can be found on steep solar slopes. Weaker layers like the Jan.17 surface hoar/facets linger down 40-60 cm in some locations, but are currently lying dormant. A weak basal snowpack exists in thin snowpack areas.

Avalanche Summary

The loose dry problem remains the main concern. These avalanches are running far and entraining a substantial amount of snow, and warmer temperatures have played a role. For example, Mt St. Piran had and Rogans Gully had significant loose dry slides over the last 48 hours.

Confidence

Problems

Loose Dry

Cold weather has created weak, faceted surface snow. In steep terrain, these facets are easily triggered and can gain enough mass to affect skiers and climbers.

Use caution above cliffs and terrain traps where small avalanches may have severe consequences.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2

Valid until: Mar 7th, 2019 4:00PM