Avalanche Forecast

Issued: Jan 25th, 2021 5:00PM

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

Avalanche Canada cmortenson, Avalanche Canada

Email

If winds increase late in the day Tuesday, watch for fresh wind slabs. Remember a small loose snow avalanche (sluff) or thin wind slab can have serious consequence in steep or extreme terrain and above terrain traps.  

Summary

Confidence

High - Confidence is due to a stable weather pattern with little change expected.

Weather Forecast

Another day of cloudy cool conditions before forecasted light snow and moderate wind arrives mid-week.

MONDAY NIGHT: Mainly cloudy with clear periods, light and variable wind, treeline temperatures around -10 C.

TUESDAY: A mix of sun and clouds with isolated flurries, trace to 2 cm new snow, light southwest wind picking up to moderate in the afternoon, treeline temperatures around -10 C.

WEDNESDAY: A mix of sun and clouds with scattered flurries, trace to 5 cm new snow, light to moderate southerly wind, treeline temperatures around -7 C.

THURSDAY: Mainly cloudy with scattered flurries, trace to 5 cm new snow, light to moderate southerly wind, treeline temperatures around -7 C.

Avalanche Summary

Loose dry avalanches (sluffs) in steep alpine terrain and steep treeline features are gaining mass with incremental loading and near surface faceting above surface hoar and older hard surfaces. Isolated thin wind slabs may be developing immediate lee of ridge crests with a few centimetres of low-density snow available for transport with southerly winds.

Snowpack Summary

In sheltered areas, 3-10 cm snow has buried surface hoar and other old surfaces, with accumulations of up to 15 cm in isolated or wind deposited zones. Alpine and upper treeline terrain remains heavily wind affected with scouring, sastrugi, isolated pockets of soft snow and layers of hard wind slabs. A hard crust is found below 1900 m and is buried by about 5 cm of soft snow. Cold temps continue to promote near-surface faceting that slowly softens hard surfaces, develop facets at the crust interface and weaken cornices.   

A solid mid-pack sits above a deeply buried crust and facet layers near the bottom of the snowpack (150-200 cm deep). These deeper weaknesses are currently unreactive, but have periodically produced large avalanches in alpine terrain during intense storms.

Terrain and Travel

  • Fresh wind slabs will likely form throughout the day, diligently watch for changing conditions.
  • Be carefull with sluffing in steep terrain, especially above cliffs and terrain traps.
  • Pay attention to cornices and give them a wide berth when traveling on or below ridges.

Problems

Wind Slabs

An icon showing Wind Slabs

If winds pick up Tuesday to moderate, watch for wind transport and be on the look out for fresh wind slabs in the immediate lee of windy ridge crests, along cross-loaded slopes or in steep alpine terrain. Cornices continue to weaken. 

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

Elevations: Alpine.

Likelihood

Unlikely - Possible

Expected Size

1 - 2

Valid until: Jan 26th, 2021 5:00PM