Avalanche Forecast

Issued: Jan 6th, 2022 4:00PM

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

Avalanche Canada mconlan, Avalanche Canada

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A hefty storm on Thursday night is anticipated to rapidly form slabs up high and rain down low. The snowpack will likely be fragile on Friday.

Summary

Confidence

High - We are confident the likelihood of avalanche will increase with the arrival of the forecast weather.

Weather Forecast

THURSDAY NIGHT: Cloudy with snow and rain, accumulation 50 to 70 cm above around 1000 m and rain below, 30 km/h southwest wind, treeline temperature 0 C, freezing level 1200 m.

FRIDAY: Early-morning snow and rain then clear skies, accumulation 5 to 10 cm above around 1000 m and rain below, 50 km/h west wind, treeline temperature 0 C dropping to -5 C over the day, freezing level 1200 m dropping to 300 m over the day.

SATURDAY: Cloudy with snowfall, accumulation 10 cm, 40 km/h southwest wind, treeline temperature -4 C.

SUNDAY: Early-morning snowfall then clear skies, accumulation 10 cm, 30 km/h south wind, treeline temperature 3 C, freezing level rising to 2300 m.

Avalanche Summary

No new avalanches were observed on Wednesday. We anticipate that widespread avalanche activity will result from Thursday night's rapid snow and rain loading, and that the resulting snow will be triggerable on Friday.

Snowpack Summary

50 to 70 cm of snow is forecast for Thursday night, with the snow-rain line expected to be around 1000 m. Above the snow-rain line, storm slabs are expected to rapidly form. Below, rain will soak the snowpack. This precipitation will test the layers buried on January 1, which include a hard melt-freeze crust that may sit above sugary faceted grains formed during the cold spell in late December.

The middle and base of the snowpack are strong, consisting of well-bonded snow and various hard melt-freeze crusts.

Terrain and Travel

  • Avoid all avalanche terrain during periods of heavy loading from new snow, wind, or rain.
  • The first few hours of rain will likely be the most dangerous period.
  • Dial back your terrain choices if you are seeing more than 30 cm of new snow.
  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.

Problems

Storm Slabs

An icon showing Storm Slabs

Upwards of 70 cm of snow is forecast above around 1000 m, which will rapidly form new storm slabs. These slabs are expected to remain reactive to humans over the day on Friday. Wind slabs are also expected to form near the mountain tops, from strong southwest wind.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

1 - 2.5

Loose Wet

An icon showing Loose Wet

Rain is forecast to soak the snowpack below around 1000 m. Loose wet avalanche activity is expected to occur during the rain event, with the likelihood decreasing over Friday as the air temperature cools.

Aspects: All aspects.

Elevations: Below Treeline.

Likelihood

Very Likely

Expected Size

1 - 2

Valid until: Jan 7th, 2022 4:00PM