Avalanche Forecast

Issued: Dec 17th, 2018 5:05PM

The alpine rating is high, the treeline rating is high, and the below treeline rating is considerable. Known problems include Storm Slabs.

Avalanche Canada mbender, Avalanche Canada

The storms keep coming. Monday night into Tuesday could bring another 30+ cm combined with strong winds. As a result, the avalanche danger will remain elevated.

Summary

Confidence

Moderate - Forecast snowfall amounts are uncertain on Tuesday

Weather Forecast

MONDAY NIGHT: Snow, accumulation 15-25cm. Alpine temperature -4. Moderate to strong south wind. Freezing level 1200m. TUESDAY: Snow, accumulation 5-15cm. Alpine temperature -2. Moderate southwest wind. Freezing level 1400m. WEDNESDAY: Flurries, accumulation 5cm. Alpine temperature -2. Light west wind. Freezing level 1300m. THURSDAY: Snow, accumulation 20-30cm. Alpine temperature -1. Moderate to strong southwest wind. Freezing level 1500m.

Avalanche Summary

Recent reports indicate numerous explosives controlled storm slab avalanches size1.5-2 at tree line and in the alpine on Monday. A few of these have have been suspected to be running on a layer of facets buried up to metre deep. Expect the likelihood of natural and human triggered storm snow avalanches to increase as we get another storm Monday night through Tuesday.

Snowpack Summary

Up to 2 m of snow has accumulated over the past week. We are in the midst of another series of storms impacting the region, which will bring another round of snow and strong to extreme southerly winds.A weak layer of facets and surface hoar lies below all the recent storm snow. Initially, avalanches were reported to be running on this layer. However, recent avalanche activity is running in the storm snow above this layer. Still, the presence of this layer shouldn't be completely discarded, since it could potentially increase expected avalanche size with a large trigger like a cornice collapse.

Problems

Storm Slabs

An icon showing Storm Slabs
The forecast weather will drive another round of storm- and wind-slabs in alpine and treeline areas. Upper parts of below treeline could also experience storm slab issues as the snowpack continues to build in this elevation band.
The new snow will require several days to settle and stabilize.Whumpfing, shooting cracks and recent avalanches are all strong inicators of unstable snowpack.Minimize overhead exposure during periods of heavy loading from new snow, wind.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely - Very Likely

Expected Size

1.5 - 3

Valid until: Dec 18th, 2018 2:00PM