Avalanche Canada ghelgeson, Avalanche Canada

South Coast Avalanche Forecast

Jan 13th, 2020 4:00PM

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

It is uncertain how well the recent storm snow is bonding with the old surface. Best to give the snowpack time to stabilize and gain strength before committing to bigger avalanche terrain.

Summary

Confidence

Moderate - Uncertainty is due to how quickly the snowpack will recover and gain strength.

Weather Forecast

After a stormy period it looks like the intensity of the weather will briefly back off until Tuesday night before a series of storms line up for the rest of the week and into the weekend.

MONDAY NIGHT: Freezing level at valley bottom, light northwest wind at most elevations, moderate west wind at ridgetop, no significant precipitation expected.

TUESDAY: Overcast, freezing level at valley bottom, light west/northwest wind at most elevations, moderate west wind at ridgetop, 1 to 5 cm of snow possible during the day, 8 to 15 cm possible Tuesday night.

WEDNESDAY: Broken cloud cover at dawn with some clearing in the afternoon, freezing level at valley bottom, strong south/southeast wind, 1 to 3 cm of snow possible during the day, 5 to 15 cm of snow Wednesday night.

THURSDAY: Broken cloud cover, freezing level around 500 m, strong south/southwest wind, 3 to 6 cm of snow possible.

Avalanche Summary

On Sunday storm slabs were quite touchy, more details in these MIN reports. Natural storm slab avalanches with crowns up to 40 cm in depth were also reported.

On Saturday, a few small (up to size 1.5) explosive triggered storm slab avalanches were reported.

Snowpack Summary

Up to 100 cm of snow fell over the last few days with moderate to strong wind first out of the south, then out of the north. There is uncertainty how well the new snow will bond with the old snow surface, as it is resting on a hard melt-freeze crust below 1500 m and potentially feathery surface hoar above the crust. Assess the bond of the recent snow before committing to avalanche terrain and travel conservatively.

Terrain and Travel

  • Use small low consequence slopes to test the bond of the new snow.
  • Give the new snow time to settle and stabilize before pushing into bigger terrain.
  • Avoid terrain traps where the consequence of any avalanche could be serious.

Problems

Storm Slabs

An icon showing Storm Slabs

Likelihood

Likely

Expected Size

1 - 2

Up to 100 cm of snow fell over the past days. This storm was accompanied by moderate to strong wind first out of the south, then out of the north. Storm slabs might still be sensitive to human traffic, particularly in lee terrain features.

The recent snow may not bond well to the snowpack, as it is resting on a hard melt-freeze crust and potentially surface hoar. Best to give all this recent snow some time to settle and strengthen before travelling into avalanche terrain.

Aspects:

All aspects.

Elevations:

All elevations.

Valid until: Jan 14th, 2020 5:00PM