Avalanche Forecast

Issued: Apr 15th, 2023 4:00PM

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

Avalanche Canada jsmith, Avalanche Canada

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Lingering wind slabs may remain reactive to human triggers on lee aspects in the alpine.

Avoid steep, rocky, and wind affected areas where triggering slabs are more likely.

Summary

Confidence

Moderate

Avalanche Summary

No avalanches were reported on Friday.

A size 3 persistent slab avalanche was reported on a southeast aspect in the alpine west of Kelsall lake on Thursday. It was suspected to have been triggered by solar radiation.

Observations are limited at this time of year, please consider sharing any information or photos you have on the Mountain Information Network to help guide our forecasts.

Snowpack Summary

20-30 cm of recent snow and light to moderate south wind may have formed wind slabs in isolated lee features in the alpine.

The recent snow sits over previously wind-affected snow surfaces on northerly aspects and sun crust on other aspects.

A weak layer of surface hoar/crust/facets buried in early January is now around 100 cm down in most areas. Operators continue to monitor this layer. A significant warming event or a large trigger (like a falling cornice) are the most likely things to activate this layer.

Weather Summary

Saturday Night

Partly cloudy with isolated flurries; 0-10 cm / 20 km/h south ridgetop wind / Temperature at treeline around -8 C / Freezing level valley bottom

Sunday

Mix of sun and cloud with isolated flurries; 0-10 cm / 10 km/h east ridgetop wind / Temperature at treeline around -4 C / Freezing level 900 m

Monday

Mix of sun and cloud / 10 km/h northwest ridgetop wind / Temperature at treeline around -4 C / Freezing level 800 m

Tuesday

Snow; 10-15 cm / 20 km/h northeast ridgetop wind / Temperature at treeline around -2 C / Freezing level 1100 m

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Avoid freshly wind loaded terrain features.
  • Avoid steep, rocky, and wind effected areas where triggering slabs is more likely.
  • Cornice failure may trigger large avalanches.

Problems

Wind Slabs

An icon showing Wind Slabs

Lingering wind slabs may remain reactive to human triggers on lee aspects in the alpine.

Aspects: North, North East, East, South East, North West.

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Persistent Slabs

An icon showing Persistent Slabs

A weak layer of surface hoar/crust/facets buried in early January is now around 100 cm down in most areas.

Operators continue to monitor this layer. A significant warming event or a large trigger (like a falling cornice) are the most likely things to activate this layer.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Unlikely

Expected Size

2 - 3

Valid until: Apr 16th, 2023 4:00PM