Avalanche Forecast

Archived

Dec 3rd, 2019–Dec 4th, 2019

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely.

Below Treeline

Natural avalanches unlikely.

Alpine

Natural avalanches unlikely, human triggered possible.

Treeline

Natural avalanches unlikely.

Below Treeline

Natural avalanches unlikely.

Regions

South Coast Inland.

Higher elevation terrain may be accumulating enough snow for dangerous avalanche conditions.

Confidence

Moderate - Uncertainty is due to the timing, track, & intensity of the incoming weather system.

Weather Forecast

TUESDAY NIGHT: 10-15 cm of snow, 60 km/h wind from the west, snow line around 1000 m in the north and 1200 m in the south

WEDNESDAY: Clearing in northern parts of the region and flurries continue with another 10 cm of snow or rain in southern parts of the region, light wind from the northwest, alpine temperatures drop to -5 C.

THURSDAY: Mix of sun and cloud, light wind from the southwest, alpine high temperatures around -5 C.

FRIDAY: Cloudy, 40 km/h wind from the southwest, alpine high temperatures around -2 C.

Avalanche Summary

Minimal avalanche activity has been reported over the past week as the snowpack is generally thin and the weather has been benign. Some parts of the region could receive enough new snow over the next few days to form slabs at higher elevations. The greatest concern will be in wind affected terrain and where the snow falls onto smooth surfaces (such as glaciers, rock slabs, and areas where there is already enough snow to cover rocks and trees).

Snowpack Summary

Less snow will make its way into the South Coast Inland region than areas closer to the coast. A total of 15-30 cm of fresh snow is possible by Wednesday afternoon, with deeper deposits in wind affected terrain. Even with this new snow, snowpack depths will remain quite thin throughout the region. Current snowpack depths are around 50 cm at upper treeline elevations, with many rocks and trees sticking out at lower elevations. In the alpine you can find slightly deeper pockets where wind has formed hard wind slabs.

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.