Avalanche Forecast

Archived

Feb 24th, 2025–Feb 25th, 2025

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Regions

South Rockies, Akamina, Bull, Crowsnest North, Crowsnest South, Elkford East, Elkford West.

Minimize your exposure to wind affected slopes.

Fresh and reactive wind slabs are expected to form and persistent weak layers remain a concern.

Confidence

Moderate

Avalanche Summary

On Sunday, storm and persistent slab avalanches were reported to size 2, both naturally and human triggered. Avalanches occurred within the storm snow and on the buried weak layer from late January. Lower elevations saw wet avalanche activity due to rainfall.

We expect natural activity to taper off, but human triggering to remain possible especially in wind affected features.

Snowpack Summary

Storm totals are expected to reach 45 cm by Tuesday afternoon. Moderate to strong west/southwest winds have redistributed this snow into deep deposits at treeline and above, likely stripping slopes that face into the wind. Below 1600 m precipitation mostly fell as rain.

A persistent weak layer of surface hoar or facets from late January is buried 40 to 60 cm deep (see photo below). This layer is expected to be more reactive with the warmer temperatures and new snow/ rain. The mid and lower snowpack is generally well settled.

Check out this MIN for recent conditions near Coleman.

Weather Summary

Monday Night

Cloudy with 5 cm of snow possible. 30 to 40 km/h southwest ridgetop wind. Freezing level 1500 m.

Tuesday

Cloudy with up to 5 cm of snow possible. 40 to 50 km/h southwest ridgetop wind, easing slightly over the day. Treeline temperature -3 °C. Freezing level rising to 1700 m.

Wednesday

Mostly clear skies with 30 km/h southwest ridgetop wind. Freezing levels rise to 2000 m, treeline temperatures of +1 °C.

Thursday

Mostly clear skies with increasing afternoon cloud. 50 to 70 km/h southwest ridgetop wind. Freezing levels rise to 2100 m, treeline temperatures of +2 °C.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Watch for newly formed and reactive wind slabs as you transition into wind-affected terrain.
Avoid steep, rocky, and wind-affected areas where triggering slabs is more likely.
Fresh snow rests on a problematic persistent slab, don't let good riding lure you into complacency.

Problems

Wind Slabs

Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.

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.