Avalanche Forecast

Issued: Jan 27th, 2023 2:00PM

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

Avalanche Canada mkoppang, Avalanche Canada

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5-15cm of storm snow fell over the past 24hrs with light winds from the north. A few cms more snow may fall overnight but amounts are not expected to be significant. Thinly covered snowpack areas are now harder to see.

Summary

Confidence

Moderate

Avalanche Summary

A few loose dry avalanches at treeline and below up to size one. One isolated sz 1 windslab in an alpine feature near Mt Chester.

Snowpack Summary

On average 10cm of new snow fell at treeline with some areas seeing more and some a bit less. Valley bottoms (where snow is needed the most) was where it was less with only around 5cm accumulation. This new snow is overlying a thin melt freeze crust up to 2100m but so far the bond appears to be good. The upper snowpack continues to strengthen with the only notable sheer at the interface with the deeper weak facets in the moderate range. Isolated windslabs were observed in alpine areas on southern aspects from the recent northerly winds but they do not extend far downslope.

As the snowpack above the weaker base becomes more cohesive the potential for wide propagation increases. This will be a common theme this winter and you should always be thinking about consequences of an avalanche.

Weather Summary

A surface ridge of high pressure over Alberta will keep conditions cold with daytime highs around -21C. Expect mainly cloudy skies with light flurries across the Rockies with the help of some northeasterly upslope flow. Unfortunately the storm is over and what remaining flurries we are expected to get, won't accumulate too much. Winds will be in the moderate range out of the NW.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Avoid shallow, rocky areas where the snowpack transitions from thick to thin.
  • Be aware of the potential for surprisingly large avalanches due to deeply buried weak layers.
  • If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.

Problems

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

Thin areas are where this layer will be easiest to trigger. Be thinking about wide propagations as the snowpack above is more cohesive that before...

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 3

Wind Slabs

An icon showing Wind Slabs

Windslabs in alpine terrain along ridgelines. Reverse loading has these on Southern aspects.

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

Elevations: Alpine.

Likelihood

Possible - Likely

Expected Size

1 - 1.5

Valid until: Jan 28th, 2023 4:00PM