Avalanche Forecast

Issued: Feb 21st, 2023 4:00PM

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

Avalanche Canada mconlan, Avalanche Canada

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Wind slabs are found on atypical south to west slopes due to strong northeast wind. The consequence of being caught in an avalanche is even higher during cold weather.

Summary

Confidence

Moderate

Avalanche Summary

Numerous small to large (size 1 to 2) storm and wind slab avalanches were observed, likely releasing within the past few days.

Looking forward, we anticipate that the northeast wind is forming wind slabs that could be triggered by riders on south to west slopes. These slopes are atypical for a wind slab problem so use caution when in wind exposed terrain.

Snowpack Summary

Strong northeast wind is redistributing the 40 to 80 cm of recent storm snow into wind slabs on southerly slopes. Very cold weather may allow for these slabs to linger for longer than is typical.

The mid-pack is gaining strength and consists of rounding facets and decomposing melt-freeze crusts.

A weak layer of large and weak facets is found near the base of the snowpack. The latest observed avalanche was in early February. Although the likelihood of triggering this layer is low, the consequence of doing so would be high. This layer is most likely to be human-triggered in thin, rocky slopes at alpine and upper treeline elevations.

Weather Summary

Tuesday Night

Clear skies with no precipitation, 40 km/h northeast wind, treeline temperature -27 °C.

Wednesday

Clear skies with no precipitation, 40 km/h northeast wind, treeline temperature -29 °C.

Thursday

Partly cloudy with no precipitation, 50 km/h northeast wind, treeline temperature -30 °C.

Friday

Increasing clouds with afternoon snowfall, trace accumulation, 50 km/h west wind, treeline temperature - 20 °C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Expect slab conditions to change drastically as you move into wind exposed terrain.
  • If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
  • Avoid shallow, rocky areas where the snowpack transitions from thick to thin.

Problems

Wind Slabs

An icon showing Wind Slabs

Strong northeast wind formed wind slabs on atypical south to west slopes. These slabs could linger longer than usual due to cold weather. Assess for slabs in steep terrain prior to committing.

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

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

A layer of large, weak facets sits near the base of the snowpack. The consequence of triggering this layer would be high. You are most likely to trigger this layer on thin, shallow, rocky slopes.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2.5 - 4

Valid until: Feb 22nd, 2023 4:00PM