Dashboard Regions Weather Stations Radar Alerts Glossary
Contact About
Log In

Register for an account and never miss a forecast again!

Register

Avalanche Forecast

Archived

Dec 7th, 2019–Dec 8th, 2019

Alpine
Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches unlikely.
Below Treeline
Natural avalanches unlikely.
Alpine
Natural avalanches possible, human triggered probable.
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

Sea To Sky.

Strong southerly wind has formed reactive wind slab at upper elevations. 

Confidence

High -

Weather Forecast

SATURDAY NIGHT: Cloudy with some flurries, 30 km/h wind from the west, alpine temperature at -4 C, freezing level is lowering to valley bottom.

SUNDAY: Mix of sun and cloud, 30 km/h wind from the north, alpine high temperatures around -3 C, freezing level at 1200 m.

MONDAY: Mix of sun and cloud, light wind from the west, alpine high temperatures around +2 C, freezing level at 1600 m.

TUESDAY: Cloudy with isolated flurries, 30 km/h wind from the southwest, alpine high temperatures around -3 C, freezing level at 1200 m.

Avalanche Summary

Several small slab avalanches were triggered remotely by humans on unsupported slopes on northern aspects in the alpine on Saturday. They were 20-50 cm thick.

A few small (size 1) slab avalanches were triggered by skiers and explosives on Wednesday. They were 20-30 cm thick and ran on a hard crust.

Snowpack Summary

The last storm brought up to 10-15 cm of new snow with strong southerly winds at upper elevations in the last few days. The new snow is heavy due to the warm temperatures. Not to far beneath this new snow is a hard crust that formed in late November. Recent snowpack tests have shown notable results on this crust. The snow above this crust is weak and provides a bed surface for avalanches to run on. Whumpfing and shooting cracks were reported in the alpine. 

Typical snowpack depths in the alpine currently range between 50 and 150 cm, depending on the amount of wind affect. Snowpack depths taper quickly with elevation as most below treeline terrain is still below the threshold for avalanches.

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.