Avalanche Forecast

Archived

Mar 10th, 2021–Mar 11th, 2021

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.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches unlikely, human triggered possible.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Regions

South Coast Inland.

Wind slabs remain a concern at upper elevations. Watch for denser, deeper drifts near ridge-crests and rollovers.

Minimize your exposure to cornices and sun-exposed slopes during the heat of the day.

Confidence

Moderate - Confidence is due to a stable weather pattern with little change expected.

Weather Forecast

WEDNESDAY NIGHT - Mainly clear with cloudy periods / light to moderate northeast wind / alpine low temperature near -8

THURSDAY - Mainly sunny / light northwest wind / alpine high temperature near -4 / freezing level 1300 m

FRIDAY - Cloudy with sunny breaks / light to moderate southwest wind / alpine high temperature near -3 / freezing level 1600 m in the north, 2000 m in the south

SATURDAY - A mix of sun and cloud / moderate south wind / alpine high temperature near 0 / freezing level 2300 m

Avalanche Summary

In the north of the region:

There were a few reports of small dry loose avalanches on Monday.

There were several reports of small to large (up to size 2.5) storm slab avalanches releasing naturally on a variety of aspects and elevations during the storm over the past weekend. Small loose dry sluffs were also observed in steep terrain.

In the south of the region:

There were numerous reports of large (size 2-3) natural glide slab avalanches over the past week, including a few more on Monday. Glide slabs are most likely in areas of smooth ground cover such as rock slabs and can be large, involving the full depth of the snowpack. Carefully consider your access/egress routes where they cross under large paths.

Snowpack Summary

Wind slabs can be found on leeward slopes at upper elevations and may still be possible to trigger. Massive cornices exist on ridgelines, which can also act as triggers on slopes below. Solar aspects likely have a crust on the surface.

In the north of the region, a weak layer of facets buried in mid-February may still be found on north aspects near treeline but has been gaining strength. The lower snowpack is generally well settled and strong.

In the south of the region, the mid and lower snowpack is generally well consolidated with no concerns of buried weak layers.

Terrain and Travel

Avoid freshly wind loaded features, especially near ridge crests, roll-overs and in steep terrain.
Back off if you encounter whumpfing, hollow sounds, or shooting cracks.
Minimize your exposure time below cornices.
Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet

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.