Avalog Join
Archived

Avalanche Forecast

Mar 20th, 2018–Mar 21st, 2018
Alpine
2: Moderate
The avalanche danger rating in the alpine will be moderate
Treeline
1: Low
The avalanche danger rating at treeline will be low
Below Treeline
1: Low
The avalanche danger rating below treeline will be low
Alpine
3: Considerable
The avalanche danger rating in the alpine will be considerable
Treeline
2: Moderate
The avalanche danger rating at treeline will be moderate
Below Treeline
1: Low
The avalanche danger rating below treeline will be low
Alpine
3: Considerable
The avalanche danger rating in the alpine will be considerable
Treeline
3: Considerable
The avalanche danger rating at treeline will be considerable
Below Treeline
2: Moderate
The avalanche danger rating below treeline will be moderate

Regions: North Columbia.

Your hunt for sheltered snow is likely to lead you to the same areas where storm slabs are a concern. Stick to supported slopes to limit your exposure.

Confidence

High -

Weather Forecast

Wednesday: Mainly cloudy with isolated flurries and a trace of new snow. Light to moderate southeast winds, increasing overnight. Freezing level to 1600 metres with alpine high temperatures around -4.Thursday: Mainly cloudy with isolated flurries and a trace of new snow, increasing overnight. Moderate to strong southeast winds. Freezing level to 2100 metres with alpine high temperatures around 0 to +1.Friday: Mainly cloudy with continuing isolated flurries and a trace of new snow. Light to moderate southwest winds. Freezing level to 1300 metres with alpine high temperatures around -7.

Avalanche Summary

Reports from Sunday included a remotely (from a distance) triggered 25 cm deep storm slab (size 1) releasing with skier traffic on a steeper north-facing slope at around 2000 m in the Monashees. Several more natural size 2 storm slab releases were observed on very steep northeast-facing terrain at around the same elevation. These occurred during the peak of daytime warming.On Saturday there were numerous reports of size 1-2, loose wet avalanches on sunny, solar aspects involving the recent storm storm snow, as well as one report of a size 1.5 skier triggered slab (30 cm deep) on a northwest aspect at 2000 m.Last Friday there were reports of several skier triggered (size 1-1.5) avalanches from 15-25 cm deep on north through southeast aspects between 1700-2100 m.

Snowpack Summary

Recent light snowfalls have been followed by warm daytime temperatures and glimpses of sun, setting up a couple of thin storm snow layers over temperature and sun crusts at lower elevations and on south aspects. On shaded aspects at higher elevations, these snowfalls have buried and preserved a couple of surface hoar layers now found up to 30 cm deep. The deepest of these surface hoar layers has been the failure plane in several recent slab avalanches.New snow amounts taper with elevation and below 1800 m, minimal accumulations have buried a supportive crust on all aspects. This crust will likely break down with daytime warming, becoming moist in the afternoon. Deeper persistent weak layers from January and December are generally considered dormant, but could wake up with a surface avalanche stepping down, large cornice fall, or a human trigger in a shallow or variable-depth snowpack area. These layers consist of sun crust, surface hoar and/or facets.

Avalanche Problems

Storm Slabs

Isolated pockets of surface hoar on sheltered, high north aspects have led to prolonged reactivity in storm slabs about 30 cm deep. Isolated wind slabs and mature cornices are other hazards to manage at higher elevations.
Give cornices a wide berth when travelling on or below ridges.Use extra caution in the afternoon if snow becomes moist or wet.Be cautious around steep or convex slopes where buried surface hoar may be preserved.

Aspects: North, North East, East.

Elevations: Alpine, Treeline.

Likelihood: Possible

Expected Size: 1 - 2