Avalanche Forecast

Issued: Mar 1st, 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 and Wind Slabs.

Tim Haggarty, Parks Canada

Banff Yoho Kootenay.

The invasion of the Arctic air back over the divide felt like a Lion today,,, or was it a Groundhog? It would seem the February cold snap is not finished with us yet.

Summary

Weather Forecast

Arctic air pushed back through from the prairies Friday with cold heavy air flowing up the main valleys squeezing small amounts of snow out of the retreating Pacific air. This Arctic air will dominate through the weekend before it begins to retreat. Light winds and sunny skies should make this tolerable if you can endure the cold start.

Snowpack Summary

Cold temperatures continue to weaken the surface snow. Wind effect is common in the alpine and several recent crusts can be found on steep solar slopes. Despite the weakening slab above it, Jan 17 surface hoar lingers down 40-60 cm in isolated locations and produces hard, resistent shears. A weak basal snowpack exists in thin snowpack areas.

Avalanche Summary

No reports of slab avalanches have come in today however loose snow avalanches or 'point release sluffs' have become common in steep terrain. Given the right terrain these sluffs can amount to significant avalanches: they start slow but gain mass quickly and would be very 'real' for those caught in a terrain trap such as above a cliff or in a gully

Confidence

Problems

Loose Dry

A sustained period of cold weather has created weak, dry, faceted surface snow. In steep terrain, these facets are easily triggered and can quickly gain enough mass to affect skiers and climbers, especially in gullies.

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

Wind Slabs

We expect a few lingering windslabs, but for the most part these slabs are old and are likely only to be found in very steep or extreme terrain near wind exposed ridge crests. Pay close attention to the feeling of the surface snow under your feet.

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

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely

Expected Size

1 - 2

Valid until: Mar 2nd, 2019 4:00PM