Avalanche Forecast

Archived

Apr 14th, 2025–Apr 15th, 2025

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Below Threshold.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely.

Below Treeline

Below Threshold.

Alpine

Natural avalanches unlikely.

Treeline

Natural avalanches unlikely.

Below Treeline

Below Threshold.

Regions

Little Yoho.

Start and finish early to enjoy the good travel and skiing conditions!

Clouds may help keep things cool, but higher freezing levels and any solar radiation will increase the likelihood of avalanches as the day progresses on Tuesday.

Confidence

Moderate

Avalanche Summary

Some small wet loose avalanches out of steep solar terrain on Monday afternoon.

On Saturday, skiers in the Ferris Glacier area remote-triggered a wind slab 60 cm deep on NE alpine terrain at ~2750 m.

On Friday, skiers remotely triggered a wind slab at ~2850 m on St. Nicholas size 2.5 that stepped down to deeper layers in a rocky area, and occurred on steep, unsupported ENE facing terrain.

Snowpack Summary

Crusts on solar aspects to ridgetop, with crusts on all aspects at treeline and below. 20-40 cm of dry snow on north-facing alpine slopes with some wind slabs in alpine lee areas.

A stiff midpack sits over a weaker layer of Jan facets in some places, but this is mainly a concern in thin snowpack areas. On all but high north aspects, crusts in the upper snowpack overlay this midpack slab. If these crusts are thick, and remain frozen, they provide good strength over the weakness.

Weather Summary

Mostly clear Monday night. Freezing levels stay fairly high, around 2000 m. Treeline temperatures down to -5°C with moderate W winds in the alpine.

Becoming a mix of sun and cloud on Tuesday morning with freezing levels going back up to ~2400 m. Light flurries begin later in the afternoon. Moderate W winds in the alpine through the day. Treeline temperatures up to +2°C.

Terrain and Travel Advice

Back off slopes as the surface becomes moist or wet with rising temperatures.
Watch for newly formed and reactive wind slabs as you transition into wind-affected terrain.

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.

Loose Wet

Loose Wet avalanches are the release of wet unconsolidated snow or slush. These avalanches typically occur within layers of wet snow near the surface of the snowpack, but they may quickly gouge into lower snowpack layers. Like Loose Dry Avalanches, they start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-wet avalanches include point-release avalanches or sluffs. Loose Wet avalanches can trigger slab avalanches that break into deeper snow layers.

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.