Banff Yoho & Kootenay National Park Avalanche Forecast

Issued: Apr 11th, 2021 4:00PM

Sun Apr 11th Current Conditions
Alpine Moderate Treeline Low Below Treeline Low
Mon Apr 12th 2 Day Outlook
Alpine Moderate Treeline Low Below Treeline Low
Tue Apr 13th 3 Day Outlook
Alpine Moderate Treeline Moderate Below Treeline Moderate

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

Excellent April ski conditions continue! Still a few things to watch for in the snowpack since cooler temperatures have limited the transition to a true spring snowpack at higher elevations. Keep watching for anomalies and enjoy the great week ahead.

Summary

Weather Forecast

Light easterly winds will develop Monday with mainly cloudy skies, a few flurries and continued cool temperatures through the day. Only a couple cm's of new snow is expected. Treeline temperatures should stay around -5 to -8 C. A clearing trend is expected to start on Tuesday.

Snowpack Summary

15 to 30 cm of storm snow at treeline with more at higher elevations. Buried crusts up to 1800m on all aspects and to ridge crest on solar aspects. Small wind slabs in alpine lee areas. Several persistent layers exist in the mid to lower snowpack that can be a concern in thin areas, with significant warming or with larger triggers like cornices.

Avalanche Summary

No new avalanches observed on Sunday. Evidence of previous loose dry avalanches in steep alpine terrain with a few cornice failures occasionally pulling slabs in steep alpine features during the recent storm. A couple avalanches were also observed in the past few days with storm snow on a crust so this is worth monitoring.

Confidence

Due to the number and quality of field observations

Problems

Wind Slabs

An icon showing Wind Slabs

Likelihood

Possible

Expected Size

1 - 2

Up to 40 cm of recent snow with previous moderate to strong winds have formed wind slabs in the alpine that may now be covered with soft snow. They seem to be bonding to the previous surfaces but are worth watching for in steep alpine lee areas.

  • Be careful with wind loaded pockets, especially in steep confined alpine terrain.

Aspects:

All aspects.

Elevations:

Alpine.

Persistent Slabs

An icon showing Persistent Slabs

Likelihood

Possible - Unlikely

Expected Size

1.5 - 3

Its been a few days since slides on the deeper weak layers were observed, but they left an impression on us. High alpine thin snowpack areas or places where a large cornice might have enough punch to trigger the deeper layers are the main concern.

  • Pockets of persistent slabs linger on alpine lee features.
  • Pay attention to overhead hazards like cornices which could trigger persistent slabs.

Aspects:

All aspects.

Elevations:

Alpine.

Valid until: Apr 12th, 2021 4:00PM

Forecast Trend

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