Avalanche Forecast

Archived

Apr 7th, 2023–Apr 8th, 2023

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Alpine

Natural and human triggered avalanches likely.

Treeline

Natural and human triggered avalanches likely.

Below Treeline

Natural avalanches possible, human triggered probable.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Regions

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

Avalanche danger will increase throughout the day as another storm will affect the region.

Recent snowfalls are stacking up in localized areas, generating dangerous conditions.

Confidence

Moderate

Avalanche Summary

Explosive controls and ski cuts produced several storm/wind slabs (size 1 to 1.5) Friday around Whistler. Thursday, pockets of hard wind slabs were triggered at treeline and above on lee slopes near ridgelines.

If you head out in the backcountry, consider sharing your observations with us on the Mountain Information Network!

Snowpack Summary

20-25 cm of new snow was received Thursday night at elevations above 1700 m. Wet snow or crusty surface formed at lower elevations on all aspects due to high freezing levels. At upper elevations, shady wind-sheltered areas may still hold dry, low-density snow. Strong winds distributed the recent snow into pockets of wind slabs near ridge tops. This new snow overlies on a variety of surfaces, including melt-freeze crust on southerly aspects, wind-affected snow on open slopes and leeward features.

The middle of the snowpack is strong and bonded. At the bottom of the snowpack, a layer of weak facets remains present and continues to be monitored for signs of reactivity.

Weather Summary

Wet, warm & windy conditions will continue to impact the region as two more storms will roll into the South Coast ranges over the weekend.

Friday night

Cloudy. Isolated flurries up to 5 cm. Moderate southwest wind gusting 40 km/h. Alpine low -3 °C. Freezing level around 1400 m.

Saturday

Snow. Local amount 15-25 cm. Strong southerly wind gusting 50 km/h. Alpine low -4 °C. Freezing level around 1200 m.

Sunday

Snow. Local amount 30-40 cm. Strong southerly wind gusting 50 km/h. Alpine low -2°C. Freezing level around 1500 m.

Monday

Cloudy. Isolated flurries. Moderate southwest wind gusting 30 km/h. Alpine high -6 °C. Freezing level around 1000 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

Avoid areas with overhead hazard.
Continue to make conservative terrain choices while the storm snow settles and stabilizes.
Be aware of the potential for loose avalanches in steep terrain where snow hasn't formed a slab.
The more the snow feels like a slurpy, the more likely loose wet avalanches will become.

Problems

Storm Slabs

Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-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.