Avalanche Forecast

Issued: Mar 13th, 2020 4:00PM

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

Avalanche Canada mconlan, Avalanche Canada

Strong northeast wind has formed wind slabs on atypical aspects. Cold air may limit solar influence, but use caution if the snow moistens.

Summary

Confidence

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

Weather Forecast

FRIDAY NIGHT: Partly cloudy with isolated flurries, moderate to strong northeast wind, alpine temperature -16 C.

SATURDAY: Clear skies, moderate northeast wind, alpine temperature -15 C.

SUNDAY: Clear skies, light to moderate northeast wind, alpine temperature -10 C.

MONDAY: Clear skies, light to moderate northeast wind, alpine temperature 0 C, freezing level rising to 2000 m.

Avalanche Summary

A few cornices were triggered by explosives on Friday. They did not trigger slabs on the slopes below, but did entrain some snow. Otherwise, small wind slabs were triggered naturally and by skiers. They were reported to be touchy but did not propagate far or produce thick slabs.

For the remainder of the weekend, it will be possible for humans to trigger wind slab avalanches as fresh wind slabs form from strong northeast wind.

Snowpack Summary

Wind slabs may be found on all aspects due to variable wind directions. Recent wind has blown from the northeast, forming fresh wind slabs in south to southwest terrain features at higher elevations. In sheltered terrain, about 30 cm of snow may overly a melt-freeze crust and potentially small surface hoar crystals.

Weak faceted snow and melt-freeze crusts exist near the base of the snowpack in some of the region, particularly the eastern and northern parts. This layer is considered dormant, as it hasn't produced an avalanche since February 20th. This layer may require a very large load, such as a cornice fall, or rapid weather changes to reactivate.

Terrain and Travel

  • Be carefull around freshly wind loaded features.
  • Recent wind has varied in direction so watch for wind slabs on all aspects.
  • Approach steep open slopes at and below treeline cautiously, buried surface hoar may exist.

Problems

Wind Slabs

An icon showing Wind Slabs

Wind slabs may be found on all aspects due to previously strong southwest wind switching to strong northeast wind. Northeast wind is atypical, so you may find wind slabs in terrain features that don't typically have them. These slabs could be touchy, as they may overly a weak layer of surface hoar. Use extra caution as you approach exposed terrain features.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

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