Avalanche Forecast

Issued: Jan 2nd, 2020 4:00PM

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

Avalanche Canada shorton, Avalanche Canada

Email

Most of the region will see more rain than snow on Friday. Danger will be HIGH in areas where precipitation accumulates as snow, elsewhere wet loose avalanches are the main concern.

Summary

Confidence

Moderate - Uncertainty is due to rapidly fluctuating freezing levels.

Weather Forecast

THURSDAY NIGHT: 10-20 cm of snow before the snow levels rise to 1500 m, then heavy rain continues overnight into Friday morning (60 mm), moderate to strong wind from the south, treeline temperatures around +2 C.

FRIDAY: Heavy rain in the morning, light rain midday, then back to heavy rain in the late afternoon (bringing 24 hour totals to 60-100 mm), heavy snowfall possible above 1500 m, strong wind from the south, treeline temperatures around +3 C.

SATURDAY: Storm continues with freezing level dropping to 700 m by Saturday morning, as rain transitions back to snow expect of 20-40 cm of new snow by Saturday afternoon, moderate wind from the southwest, treeline temperatures around -2 C.

SUNDAY: Another storm pulse brings 20-30 cm of snow, moderate wind from the south, freezing level around 700 m with treeline temperatures around -2 C.

Avalanche Summary

Heavy rain will create the potential for wet loose avalanches at most elevations, while thick storm slabs will likely form in the highest peaks of the region. A few small wet loose avalanches were reported in steep terrain on Wednesday.

Snowpack Summary

The current storm is expected to deliver 10-20 cm of snow to the North Shore mountains on Thursday night before freezing levels rise and heavy rain soaks the snowpack. Heavy accumulations of wet snow are possible in terrain above 1500 m, resulting in the formation of touchy storm slabs. Snowpack depths near treeline currently range from 140-180 cm, and the snowpack diminishes rapidly with elevation.

Terrain and Travel

  • Use caution above cliffs and terrain traps where even small avalanches may have severe consequences.
  • Minimize exposure during periods of heavy loading from rain.
  • Dial back your terrain choices if you are seeing more than 30 cm of new snow.

Problems

Storm Slabs

An icon showing Storm Slabs

High elevation terrain could see over 50 cm of new snow by Friday morning, resulting in very unstable storm slabs. Storm slabs will most likely be limited to terrain above 1500 m based on the current weather forecast, but are possible at lower elevations depending on how the freezing level fluctuates.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Very Likely

Expected Size

1 - 2.5

Loose Wet

An icon showing Loose Wet

Surface snow will become unstable in steep terrain when it gets soaked by rain. Small wet loose avalanches can be dangerous above cliffs, gullies, and trees.

Aspects: All aspects.

Elevations: Treeline, Below Treeline.

Likelihood

Likely

Expected Size

1 - 1.5

Valid until: Jan 3rd, 2020 4:00PM