Avalanche Forecast

Issued: Jan 12th, 2021 4:00PM

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

Avalanche Canada swerner, Avalanche Canada

The snowpack will need time to adjust, settle and stabilize. Don't let the sunny breaks lure you into aggressive terrain as reactive storm and winds slabs may exist in the high alpine post storm.  

Summary

Confidence

Low - Uncertainty is due to rapidly fluctuating freezing levels. Uncertainty is due to the timing, track, & intensity of the incoming weather system.

Weather Forecast

The storm will start to diminish overnight as a ridge of high pressure builds on Wednesday bringing dryer and cooler conditions. 

Tuesday Night: Another 20 to 30 mm of precipitation with freezing levels peaking at 2000 m until early Wednesday morning then falling to 700 m. Ridgetop wind strong from the southwest.

Wednesday: Mix of sun and cloud. Treeline temperatures near 0 degrees and freezing level 700 m.

Thursday/ Friday: Cloudy with light precipitation. Treeline temperatures +4. Freezing level 2400 m and falling to 1700 m on Friday. Ridgetop wind strong and gusty from the West.

Avalanche Summary

No recent avalanche reports on Tuesday.

Natural avalanche activity and human triggered avalanches may persist in the alpine after the storm on Wednesday. 

Snowpack Summary

The recent storm could bring up to 100 mm of precipitation by early Wednesday morning, with it falling mostly as rain to the mountain tops. As the temperatures start to fall Tuesday night and early Wednesday morning the storm may leave snow in alpine locations. This means that only the highest peaks will receive snow. 

Above the snow-rain line, reactive storm and wind slabs likely exist. Below the snow-rain line, a rain-soaked/ saturated snowpack will exist but form a firm crust as the temperatures drop.

The remainder of the snowpack is well-consolidated.

Terrain and Travel

  • Travel in alpine terrain is not recommended.
  • Choose conservative terrain and watch for clues of instability.
  • Watch for unstable snow on specific terrain features, especially when the snow is moist or wet.

Problems

Storm Slabs

An icon showing Storm Slabs

Snow accumulation above the snow-rain line will likely build reactive slab avalanches. Slabs will be thickest in lee terrain features, as the snow will fall with strong southwest wind. 

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Very Likely

Expected Size

1 - 2.5

Loose Wet

An icon showing Loose Wet

Rain will soak the snowpack below the snow-rain line. With forecast freezing levels dropping to 700 m this may only be a problem below treeline where the snow doesn't freeze into a crust. 

Aspects: All aspects.

Elevations: Treeline, Below Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Jan 13th, 2021 4:00PM