South Coast Avalanche Forecast

Jan 3rd, 2020 4:00PM

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

Expect to find rapidly changing conditions with elevation. Travel in alpine and treeline avalanche terrain is not recommended. Travel below treeline will require conservative decision-making if you find 20 cm or more of dry snow, as it may not bond well to the snowpack.

Summary

Confidence

Moderate - Uncertainty is due to rapidly fluctuating freezing levels.

Weather Forecast

FRIDAY NIGHT: Cloudy with rain switching to snow, accumulation 10 to 30 cm, strong southwest wind, treeline temperature 0 C, freezing level 1600 m dropping to 600 m by the morning.

SATURDAY: Cloudy with light snowfall, accumulation 5 cm, moderate southwest wind, treeline temperature -4 C, freezing level 700 m.

SUNDAY: Cloudy with snowfall, accumulation 20 to 40 cm, moderate southwest wind, treeline temperature -2 C, freezing level 800 m.

MONDAY: Cloudy with snowfall, accumulation 30 to 40 cm, strong southwest wind, treeline temperature 0 C, freezing level 1100 m.

Avalanche Summary

Storm slab avalanches likely released naturally on Friday at alpine elevations, where over 70 cm of snow may have accumulated. Wet loose avalanches may have occurred at and below treeline, where the precipitation fell as rain.

Snowpack Summary

Over 70 mm of precipitation fell on the mountains on Thursday into Friday, with a freezing level around 1400 m to 1600 m. This formed rain-soaked snow below about 1400 m and thick storm slabs above. As freezing levels drop on Friday night, around 10 to 30 cm of more snow will accumulate at alpine and treeline elevations and likely closer to 5 to 10 cm at below treeline elevations.

The snowpack depth near treeline is around 140 to 180 cm, which diminishes rapidly at lower elevations.

Terrain and Travel

  • Travel in alpine terrain is not recommended.
  • Make observations and assess conditions continually as you travel.
  • Be alert to conditions that change with elevation.
  • Avoid areas with overhead hazard.

Problems

Storm Slabs

An icon showing Storm Slabs

Likelihood

Likely-Very Likely

Expected Size

1 - 2.5

Friday's storm brought mostly rain to the area, except for alpine elevations where over 70 cm of snow may have accumulated. As the freezing levels drop into Saturday, rain will switch to snow at all elevations. Around 10 to 30 cm of snow may accumulate, which could form touchy slabs that may not bond well to the underlying snow. Best to avoid alpine and treeline avalanche terrain. Below treeline, assess the amount of snow and its bond to the underlying layer as you travel prior to committing to avalanche terrain.

Aspects:

All aspects.

Elevations:

All elevations.

Valid until: Jan 4th, 2020 5:00PM