Avalanche Forecast

Archived

Mar 23rd, 2023–Mar 24th, 2023

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Alpine

Natural and human triggered avalanches likely.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches possible, human triggered probable.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Regions

Kananaskis, Bow Valley, Highwood Pass, North 40, Spray - KLakes.

Conflicting weather forecasts are keeping us on the edge of our forecasting seats. Read the entire bulletin carefully. If we are blessed with a heavy snowfall in the next 2 days, expect a widespread avalanche cycle. The ratings & discussions in this bulletin reflect a 10-15cm snowfall.

Confidence

Low

Avalanche Summary

No new avalanches observed or reported over the past 24hrs.

Snowpack Summary

Crusts. We are seeing sun crusts and temperature crusts slowly creep onto all aspects and elevations. True north is hanging in there, but most other areas are showing signs of spring. Keep in mind these crusts are superficial at this point and don't signal a spring snowpack or any true increase in stability. A thin crust isn't enough to bridge the weaker layers just yet. If we do get a decent amount of snow tomorrow expect a poor bond with the existing crusts. A cold night and cloudy skies will almost guarantee the new snow will rest on a smooth, well frozen crust. Aside from that we still have windslabs up to 40cm that are active on north aspects and the Rockies' hallmark deep persistent weak layer to worry about.

Weather Summary

Place your bets! It looks like we will get some snow tomorrow but the jury is out on how much. Some forecasts say up to 20cm by tomorrow night and others say 3cm. This a huge difference and will effect the hazard very differently. Winds will decrease through the day and settle to light winds by early afternoon. Even ridge winds will be light. Temperatures will be steady around -8. Interestingly, some forecasts are calling for potential lightening mid afternoon!

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Minimize exposure to sun-exposed slopes when the solar radiation is strong.
Avoid shallow, rocky areas where the snowpack transitions from thick to thin.
Cornices become weak with daytime heating or solar exposure.

Problems

Deep Persistent Slabs

Deep Persistent Slab avalanches are the release of a thick cohesive layer of hard snow (a slab), when the bond breaks between the slab and an underlying persistent weak layer deep in the snowpack. The most common persistent weak layers involved in deep, persistent slabs are depth hoar or facets surrounding a deeply buried crust. Deep Persistent Slabs are typically hard to trigger, are very destructive and dangerous due to the large mass of snow involved, and can persist for months once developed. They are often triggered from areas where the snow is shallow and weak, and are particularly difficult to forecast for and manage.

Persistent Slabs

Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.

Loose Dry

Loose Dry avalanches are the release of dry unconsolidated snow and typically occur within layers of soft snow near the surface of the snowpack. These avalanches start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-dry avalanches include point-release avalanches or sluffs.