Avalanche Canada shorton, Avalanche Canada

South Columbia Avalanche Forecast

Jan 15th, 2020 5:00PM

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

New wind slabs will form at higher elevations on Thursday, requiring careful route finding.

Summary

Confidence

High - The number, quality, or consistency of field observations is good, and supports our confidence.

Weather Forecast

WEDNESDAY NIGHT: 5-15 cm of low density snow, strong wind from the south, alpine temperatures around -15 C.

THURSDAY: 10-20 cm of low density snow, moderate to strong wind from the south, alpine high temperatures around -8 C.

FRIDAY: Cloudy with light flurries, light wind from the southwest, alpine high temperatures around -8 C.

SATURDAY: Light flurries with 5-10 cm of snow, moderate wind from the south, alpine high temperatures around -8 C.

Avalanche Summary

Incoming weather will refresh the wind slab problem creating fresh slabs on north and east lee features. Wind slabs have been the main story the past few days, with many small (size 1) wind slabs being triggered by riders on all aspects and elevations. A few larger (size 2) naturally triggered wind slabs have also been observed in the alpine. Persistent slab activity has tapered off, as it has been over a week since any reports of large persistent slab avalanches.

Snowpack Summary

Surface conditions are variable due to cold temperatures and shifting wind directions over the past few days. Expect fresh wind slabs to form on lee features on Thursday. A thin crust exists in many areas 50-100 cm below the surface, and beneath that is a layer of surface hoar that is roughly 80-120 cm deep in the Selkirks and 120-160 cm deep in the Monashees. A facet/crust layer from late November lingers near the bottom of the snowpack. These layers appear to be unreactive under the current conditions, but could reappear as problems in the future.

Terrain and Travel

  • Avoid freshly wind loaded features, especially near ridge crests, roll-overs and in steep terrain.

Problems

Wind Slabs

An icon showing Wind Slabs

Likelihood

Likely

Expected Size

1 - 2

Moderate flurries and strong southwest wind will form fresh wind slabs in open terrain on Thursday, especially near ridgetops.

Aspects:

North, North East, East, South East, North West.

Elevations:

Alpine, Treeline.

Valid until: Jan 16th, 2020 5:00PM