Avalanche Forecast

Archived

Apr 4th, 2025–Apr 5th, 2025

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Regions

Kootenay Boundary, Bonnington, Grohman, Kootenay Pass, Norns, Rossland, Ymir, Crawford, Moyie, St. Mary, Kokanee.

Another warm-up brings rising avalanche risk.

Uncertainty remains about cornice falls or surface instabilities stepping down to persistent weak layers.

Read the new forecasters' blog.

Confidence

High

Avalanche Summary

On Thursday, skier-triggered and natural storm slabs (up to size 1.5) occurred on northerly alpine terrain in Kookanee Provincial park.

Several dry loose avalanches continue to be triggered by skiers in steep northerly slopes, while wet loose avalanches were solar-triggered on southerly slopes.

Expect an increase in avalanche activity with the forecasted warm weather.

Snowpack Summary

A diurnal melt-freeze cycle occurred in the past days. The surface is either moist or capped with a thin crust on all aspects and elevations except for high northerly slopes where up to 30 cm overlies a thick crust from late March. Below these crusts, the upper snowpack is moist.

Several weak layers from early March, mid-February, and late January can be found in the mid and lower snowpack.

The remainder of the snowpack is generally well settled.

Weather Summary

Friday Night

Clear. 10 to 20 km/h southwest ridgetop wind. Treeline temperature -2 °C. Freezing level returning to valley bottom.

Saturday

Sunny. 20 to 30 km/h southwest ridgetop wind. Treeline temperature +4° C. Freezing level rising to 2500 m.

Sunday

Sunny. 10 to 30 km/h south ridgetop wind. Treeline temperature +8° C. Freezing level around 3000 m.

Monday

Mostly cloudy with 10 to 15 cm of wet snow or rain. 20 to 40 km/h southeast ridgetop wind. Treeline temperature +6° C. Freezing level around 2800 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Avalanche danger is expected to increase throughout the day.
Avalanche activity is unlikely when a thick melt-freeze crust is present on the snow surface.
Limit exposure to steep, sun exposed slopes, especially when the solar radiation is strong.
Avoid travelling on slopes below cornices.
Be aware of the potential for loose avalanches in steep terrain where snow hasn't formed a slab.

Problems

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.