Avalanche Forecast

Issued: Apr 11th, 2019 4:22PM

The alpine rating is moderate, the treeline rating is moderate, and the below treeline rating is low. Known problems include Loose Wet and Wind Slabs.

Avalanche Canada ldreier, Avalanche Canada

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As soon as the sun comes out the surface snow will become moist and increase the likelihood of loose wet avalanches. Wind slabs might still be sensitive to human triggering.

Summary

Confidence

High -

Weather Forecast

THURSDAY NIGHT: Mostly clear with isolated flurries / light northeast wind / alpine low -6 C / freezing level at valley bottomFRIDAY: Sunny with cloudy periods / light to moderate westerly wind / alpine high -4 C / freezing level 1700 mSATURDAY: Snow in the mountains and rain in the valleys / up to 15 cm of snow accumulation / strong southwest wind / alpine high -4 C / freezing level 1700 mSUNDAY: Cloudy / up to 5 cm snow accumulation / moderate west wind / alpine high -8 C / freezing level 1500 m

Avalanche Summary

On Wednesday, no new avalanche activity was observed. On Tuesday, a small (size 1) slab avalanche 30 cm deep was remotely triggered by a skier from 80 m away on a northeast aspect at 2250 m. A layer of small surface hoar below the most recent snow may have been the weak layer. Additionally, several loose wet avalanches up to size 1.5 were triggered on solar aspects throughout the day by strong solar radiation.On Monday there was quite a bit of natural avalanche activity in the recent storm snow. Slabs to size 1.5 were reported from all aspects between 1800 and 2700 m. The natural activity was likely caused by the appearance of the strong April sun.

Snowpack Summary

Last week's unsettled weather produced 20-35 cm of snow in the alpine which tapers rapidly with elevation. This snow is sitting on a melt-freeze crust on all aspects except for northerly slopes above 1800 m, where it sits on dry snow and possibly small surface hoar (weak, feathery crystals) in isolated locations. High elevation, north facing terrain where wind slabs may be sitting on small surface hoar might currently be the most likely place to trigger a slab avalanche.Snow is disappearing rapidly at lower elevations.

Problems

Loose Wet

An icon showing Loose Wet
Any appearance of the strong April sun can initiate a loose wet avalanche cycle. The likelihood of loose wet avalanches increases as temperatures warm through the day and once the sun comes out for a prolonged period of time.
Loose wet avalanches may start small but they can grow and push you into dangerous terrain.A moist/wet snow surface, pinwheeling and natural avalanches all indicate a weakening snowpack.Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.

Aspects: East, South East, South, South West, West, North West.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 1.5

Wind Slabs

An icon showing Wind Slabs
Up to 35 cm of snow sits on a crust in most locations, except for high elevation, north facing terrain where the old snow surface remained dry with isolated surface hoar. Wind slabs in these lee features may remain reactive to human triggers.
Pay attention to changing condition with elevation/aspect.Steep, rocky terrain with a highly variable snowpack depth are likely places to trigger these slabs.Wind slabs that are sitting on surface hoar may remain reactive to human triggers.

Aspects: North, North East.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Valid until: Apr 12th, 2019 2:00PM