Avalanche Forecast

Issued: Jan 24th, 2021 4:00PM

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

Avalanche Canada cmortenson, Avalanche Canada

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5-8cm of new snow should improve riding conditions but may also be blown into fresh wind slabs immediate lee of windy ridgecrests.  

Summary

Confidence

Moderate - Confidence is due to a stable weather pattern; little change is expected for several days. Uncertainty is due to limitations in the field data.

Weather Forecast

Continued cool temps, increasing wind and a mix of clouds, sun and isolated flurries for early in the week.  

SUNDAY NIGHT: Mostly clear skies with variable clouds, light northwest wind, treeline temperatures near -11C.  

MONDAY: Mix of sun and cloud, light east wind, treeline temperatures around -12 C.

TUESDAY: Mix of sun and cloud, light to moderate southeast wind, treeline temperatures around -13 C.

WEDNESDAY: Mix of sun and cloud with isolated flurries, moderate southeast wind, treeline temperatures around -15 C.

Avalanche Summary

A few cornice failures were observed late last week. Otherwise, no significant avalanche activity has been reported since Tuesday, when there was a cycle of natural wind slab avalanches. Sporadic deep persistent slab avalanches were reported 1-2 weeks ago (triggered with heavy loads such as explosives and cornices), but deeper weak layers appear unreactive under the current conditions.

Snowpack Summary

2-5 cm recent snow has buried surface hoar, which was reported as widespread below treeline and isolated at sheltered treeline and alpine locations. Buried sun crust can be found on steep solar. Widespread wind scoured surfaces, older wind slabs in alpine and exposed treeline locations and wind effect extending below treeline in open areas persist. Large cornices may becoming weak with cold temperatures.A thick crust exists near the surface below 1000 m. The middle snowpack is overall well settled. Some isolated surface hoar layers from mid-January, where preserved, are 20-60 cm deep. 

The lower snowpack has two decomposing crust layers that have been causing a deep persistent slab problem for most of the past month. The upper crust is 70-140 cm deep in the Smithers area and continues to show hard sudden results in snow pits. The deeper crust at the bottom of the snowpack continues to be a problem in shallow ranges like the Babines. These layers should be unreactive under the current conditions, but shallow rocky slopes should still be carefully assessed and approached with caution. 

Terrain and Travel

  • Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
  • Watch for areas of hard wind slab on alpine features.
  • Be especially cautious near rock outcroppings, on steep convexities and anywhere the snowpack feels thinner than average.
  • Caution around slopes that are exposed to cornices overhead.

Problems

Wind Slabs

An icon showing Wind Slabs

Reactive wind slabs may be found on steep alpine slopes and along ridge tops. Cornice failures from above may trigger an otherwise stubborn wind slab in addition to being a hazard outright.

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

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Valid until: Jan 25th, 2021 5:00PM