Avalanche Forecast

Archived

Mar 17th, 2025–Mar 18th, 2025

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Alpine

Natural avalanches unlikely, human triggered possible.

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.

Regions

Coquihalla, Manning.

Stay vigilant, as conditions may change rapidly if the March sun comes out.

Expect significant variability based on elevation, aspect, and exposure to wind and sun.

Confidence

Moderate

Avalanche Summary

Numerous wind slabs (size 1) were easily triggered by skiers on lee treeline features near Thar Peak and several loose wet avalanches (up to size 1.5) were sun-induced on steep southerly slopes during the weekend on the Coquihalla.

Thanks for sharing your observations via the MIN if you are going out into the backcountry.

Snowpack Summary

The region received 15 to 25 cm this past weekend, totaling up to 75 cm of recent storm snow, which is settling out rapidly. This sits above a crust on all aspects except on high, north-facing alpine terrain.

Variable conditions exist at upper elevations, from windswept to crusty surfaces, and deeper pockets of storm snow on lee slopes. Southerly slopes have been sun-affected and moist and/or heavy snow can be found.

A layer of facets and surface hoar that formed in February has been found 90 to 150 cm down, and a layer of facets and surface hoar from late January can be found down to 130 to 190 cm. No recent notable test results have been seen on these layers.

Weather Summary

Monday Night

Cloudy with isolated convective flurries. 30 to 40 km/h west ridgetop wind. Treeline temperature -6 °C. Freezing level 500 m.

Tuesday

Partly cloudy with isolated flurries. 10 to 20 km/h west ridgetop wind. Treeline temperature -3 °C. Freezing level 1000 m.

Wednesday

Mix of sun and clouds. 30 to 50 km/h south ridgetop wind. Treeline temperature 0 °C. Freezing level rising to 1500 m.

Thursday

Cloudy with 10 to 15 cm of new snow. 40 to 60 km/h southwest ridgetop wind. Treeline temperature -3°C. Freezing level 1000 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Be careful as you transition into wind-affected terrain.
Wind slabs are isolated, but may remain reactive.
Be aware of the potential for loose avalanches in steep terrain where snow hasn't formed a slab.
Back off slopes as the surface becomes moist or wet with rising temperatures.

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.