Avalanche Forecast

Archived

Mar 14th, 2024–Mar 15th, 2024

Alpine

Natural and human triggered avalanches likely.

Treeline

Natural and human triggered avalanches likely.

Below Treeline

Natural and human triggered avalanches likely.

Alpine

Natural and human triggered avalanches likely.

Treeline

Natural and human triggered avalanches likely.

Below Treeline

Natural and human triggered avalanches likely.

Alpine

Natural and human triggered avalanches likely.

Treeline

Natural and human triggered avalanches likely.

Below Treeline

Natural and human triggered avalanches likely.

Regions

Sea To Sky, Brandywine, Garibaldi, Homathko, Spearhead, Tantalus, Sky Pilot.

⚠️ Avoid all avalanche terrain ⚠️

Widespread natural avalanches continue.

Persistent slab activity is expected to increase, as temperatures remain above mountain top for several days

Confidence

High

Avalanche Summary

Large, naturally triggered persistent slab activity continued on Wednesday. A size 3 natural slab avalanche was reported on the MIN, at nearly 3 metres deep, this ran on the basal facets near the ground.

Up to size 4 avalanches have been reported from the recent warming and sunshine with wide propagation and deep crowns. Continued persistent slab activity is expected, as well as widespread loose wet avalanches and cornice failures as warming continues.

Snowpack Summary

Expect to find moist or wet snow at all elevations except high north facing terrain. Over 100 cm of snow from the past week is rapidly settling but some storm slab instabilities may still be present, especially in wind-affected areas. These will likely trigger as wet avalanches.

A weak layer composed of facets on a crust is buried 150 to 250 cm deep and remains sensitive to both human and natural triggers.

The warm temperatures are expected to increase reactivity of all buried weak layers, producing large natural avalanches.

Weather Summary

Thursday Night

Mostly clear. 25 km/h northwest ridgetop wind. Freezing levels remain above 3000 m overnight.

Friday

Mostly sunny. 15 km/h north wind. Treeline temperature +6 °C with freezing level climbing to 3300 m.

Saturday

Sunny. 45 km/h southeast ridgetop wind. Treeline temperature +9 °C with freezing level steady at 3500 m.

Sunday

Sunny. 30 km/h southeast ridgetop wind. Treeline temperature +8 °C with freezing level sustained at 3300 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Avoid avalanche terrain during periods of strong sun.
Cornice failure may trigger large avalanches.
Avoid exposure to overhead avalanche terrain, large avalanches may reach the end of run out zones.
The likelihood of deep persistent slab avalanches will increase with each day of warm weather.

Problems

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.