Avalanche Forecast

Archived

Mar 5th, 2025–Mar 6th, 2025

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 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.

Regions

Coquihalla, Harrison-Fraser, Manning, Skagit.

Carefully assess conditions as you move through the mountains

We expect solar input and warming will increase avalanche activity. We have uncertainty in size of avalanches that may occur

Confidence

Low

Avalanche Summary

Since the warm weekend, wet loose avalanches up to size 2 were observed.

No persistent slab avalanche activity has been observed since over a week ago in the Manning area.

Snowpack Summary

Up to 20 cm of new snow has fallen over a crust on all aspects and elevations. Beneath, 10 to 20 cm of snow is sandwiched between the surface and another crust.

The snow surface will likely become moist during the day on all aspects and elevations except for high north facing slopes.

A weak layer of facets and/or surface hoar is buried 50 to 120 cm deep. This layer has not produced avalanche activity for over a week but snowpack test results continued to show results, particularly in the Manning area.

A crust from December, buried 1 to 2 m deep, has been observed to be breaking down.

Weather Summary

Wednesday Night

Partly cloudy. 10 to 20 km/h north ridgetop wind. Treeline temperature -3 °C, potential for inversion with colder temperatures at valley bottom.

Thursday

Mostly Sunny. 15 to 30 km/h north ridgetop wind. Freezing level rising to 1900 m.

Friday

Mix of sun and cloud. 20 to 50 km/h southwest ridgetop wind. Treeline temperature -2 °C.

Saturday

Mostly cloudy with up to 5 mm of mixed precipitation. 50 to 70 km/h southwest ridgetop wind. Freezing level rising to 2000 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Be careful as you transition into wind-affected terrain.
If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
Use extra caution around cornices: they are large, fragile, and can trigger slabs on slopes below.
Be alert to conditions that change with elevation and sun exposure.
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.

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 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.