Avalanche Forecast

Issued: Mar 4th, 2022 4:00PM

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

Avalanche Canada shorton, Avalanche Canada

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Human triggered avalanches are possible as recent snow slowly strengthens. Danger will be heightened on sun-exposed slopes.

Summary

Confidence

Moderate - Uncertainty is due to the complexity of the snowpack’s structure.

Weather Forecast

FRIDAY NIGHT: Clear skies, light wind from the north, treeline temperatures drop to -12 C.

SATURDAY: Mix of sun and cloud, light wind from the northwest, treeline temperatures reach -5 C.

SUNDAY: Sunny, light wind from the west, treeline temperatures reach -5 C.

MONDAY: Cloudy with isolated flurries bringing up to 5 cm of snow, moderate wind from the northwest, treeline temperatures reaching -5 C.

Avalanche Summary

We have seen a gradual decline in the reactivity of storm slabs since the natural avalanche cycle on Monday and Tuesday. There were still several size 1-1.5 human triggered slabs on Thursday, involving 20 to 40 cm of recent storm snow above recently buried surface hoar and crust layers. These have occurred on all aspects and elevations, although below treeline elevations have seen more wet loose avalanches than slab avalanches recently.

Recent avalanche activity has been confined to new snow layers, with the exception of one isolated size 3 avalanche in the Esplanade Range on Tuesday (in the eastern Selkirks). Avalanches on persistent weak layers are now unlikely in most parts of the region based on recent weather trends and lack of avalanches, but some extra caution is suggested for those venturing into the eastern Selkirks.

The main concerns this weekend are lingering storm slabs, and the potential impact of sunny weather weakening sun-exposed snow and cornices.

Snowpack Summary

Recent storm snow has likely settled into 20 to 40 cm of heavy powder at upper elevations, but is becoming moist and crusty on south-facing slopes and lower elevations (below 1800 m near Revelstoke and below 1500 m near Blue River). The storm snow has shown signs of remaining reactive on some slopes where it sits above sun crusts or feathery surface hoar. The snowpack is generally well settled below the new snow, with previous persistent weak layers showing improving trends over the past weeks.

Terrain and Travel

  • If you are increasing your exposure to avalanche terrain, do it gradually as you gather information.
  • Investigate the bond of the recent snow before committing to your line.
  • Be carefull around freshly wind loaded features.
  • Minimize exposure to sun-exposed slopes when the solar radiation is strong.
  • Cornices become weak with daytime heating.

Problems

Storm Slabs

An icon showing Storm Slabs

20 to 40 cm of recent storm snow is bonding relatively quickly in most areas, but may still produce avalanches in specific terrain features. This includes steep sun-exposed slopes, wind loaded slopes, and open convexities at treeline where there could be buried sun crusts or surface hoar layers.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Mar 5th, 2022 4:00PM